Untry script

36 files changed, 199 insertions, 199 deletions

diff --git a/components/script/body.rs b/components/script/body.rs
index 80c9be5d49f..841868889d0 100644
--- a/components/script/body.rs
+++ b/components/script/body.rs
@@ -148,8 +148,8 @@ fn run_form_data_algorithm(root: &GlobalScope, bytes: Vec<u8>, mime: &[u8]) -> F
     } else {
         ""
     };
-    let mime: Mime = try!(mime_str.parse().map_err(
-        |_| Error::Type("Inappropriate MIME-type for Body".to_string())));
+    let mime: Mime = mime_str.parse().map_err(
+        |_| Error::Type("Inappropriate MIME-type for Body".to_string()))?;
     match mime {
         // TODO
         // ... Parser for Mime(TopLevel::Multipart, SubLevel::FormData, _)
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index d77f6ea931c..a44a3f54c30 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -390,7 +390,7 @@ pub unsafe fn private_from_proto_check<F>(mut obj: *mut JSObject,
                                           -> Result<*const libc::c_void, ()>
     where F: Fn(&'static DOMClass) -> bool
 {
-    let dom_class = try!(get_dom_class(obj).or_else(|_| {
+    let dom_class = get_dom_class(obj).or_else(|_| {
         if IsWrapper(obj) {
             trace!("found wrapper");
             obj = UnwrapObject(obj, /* stopAtWindowProxy = */ 0);
@@ -406,7 +406,7 @@ pub unsafe fn private_from_proto_check<F>(mut obj: *mut JSObject,
             trace!("not a dom wrapper");
             Err(())
         }
-    }));
+    })?;
 
     if proto_check(dom_class) {
         trace!("good prototype");
diff --git a/components/script/dom/bindings/mozmap.rs b/components/script/dom/bindings/mozmap.rs
index abfedf02caf..19f65ec05f8 100644
--- a/components/script/dom/bindings/mozmap.rs
+++ b/components/script/dom/bindings/mozmap.rs
@@ -69,7 +69,7 @@ impl<T, C> FromJSValConvertible for MozMap<T>
                 return Err(());
             }
 
-            let property = match try!(T::from_jsval(cx, property.handle(), config.clone())) {
+            let property = match T::from_jsval(cx, property.handle(), config.clone())? {
                 ConversionResult::Success(property) => property,
                 ConversionResult::Failure(message) => return Ok(ConversionResult::Failure(message)),
             };
diff --git a/components/script/dom/bindings/structuredclone.rs b/components/script/dom/bindings/structuredclone.rs
index 53f3b63e085..5644784e10c 100644
--- a/components/script/dom/bindings/structuredclone.rs
+++ b/components/script/dom/bindings/structuredclone.rs
@@ -114,7 +114,7 @@ unsafe fn write_blob(blob: Root<Blob>,
                      w: *mut JSStructuredCloneWriter)
                      -> Result<(), ()> {
     let structured_writer = StructuredCloneWriter { w: w };
-    let blob_vec = try!(blob.get_bytes());
+    let blob_vec = blob.get_bytes()?;
     assert!(JS_WriteUint32Pair(w, StructuredCloneTags::DomBlob as u32, 0));
     structured_writer.write_slice(&blob_vec);
     structured_writer.write_str(&blob.type_string());
diff --git a/components/script/dom/bindings/xmlname.rs b/components/script/dom/bindings/xmlname.rs
index e688052fba8..fc330b7563d 100644
--- a/components/script/dom/bindings/xmlname.rs
+++ b/components/script/dom/bindings/xmlname.rs
@@ -32,7 +32,7 @@ pub fn validate_and_extract(namespace: Option<DOMString>,
     let namespace = namespace_from_domstring(namespace);
 
     // Step 2.
-    try!(validate_qualified_name(qualified_name));
+    validate_qualified_name(qualified_name)?;
 
     let colon = ':';
 
diff --git a/components/script/dom/bluetooth.rs b/components/script/dom/bluetooth.rs
index 3c3b88a27ac..846b1ff666c 100644
--- a/components/script/dom/bluetooth.rs
+++ b/components/script/dom/bluetooth.rs
@@ -328,7 +328,7 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
 
             for service in services {
                 // Step 3.2 - 3.3.
-                let uuid = try!(BluetoothUUID::service(service.clone())).to_string();
+                let uuid = BluetoothUUID::service(service.clone())?.to_string();
 
                 // Step 3.4.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
@@ -393,7 +393,7 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
                 // Step 7.3: No need to convert to IDL values since this is only used by native code.
 
                 // Step 7.4 - 7.5.
-                map.insert(manufacturer_id, try!(canonicalize_bluetooth_data_filter_init(bdfi)));
+                map.insert(manufacturer_id, canonicalize_bluetooth_data_filter_init(bdfi)?);
             }
             Some(map)
         },
@@ -417,7 +417,7 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
                 };
 
                 // Step 9.3 - 9.4.
-                let service = try!(BluetoothUUID::service(service_name)).to_string();
+                let service = BluetoothUUID::service(service_name)?.to_string();
 
                 // Step 9.5.
                 if uuid_is_blocklisted(service.as_ref(), Blocklist::All) {
@@ -427,7 +427,7 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
                 // Step 9.6: No need to convert to IDL values since this is only used by native code.
 
                 // Step 9.7 - 9.8.
-                map.insert(service, try!(canonicalize_bluetooth_data_filter_init(bdfi)));
+                map.insert(service, canonicalize_bluetooth_data_filter_init(bdfi)?);
             }
             Some(map)
         },
diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 293e81b6e1c..be7c8e945c2 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -1137,18 +1137,18 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
                 // https://html.spec.whatwg.org/multipage/#img-error
                 // If the image argument is an HTMLImageElement object that is in the broken state,
                 // then throw an InvalidStateError exception
-                try!(self.fetch_image_data(image).ok_or(Error::InvalidState))
+                self.fetch_image_data(image).ok_or(Error::InvalidState)?
             },
             HTMLImageElementOrHTMLCanvasElementOrCanvasRenderingContext2D::HTMLCanvasElement(ref canvas) => {
                 let _ = canvas.get_or_init_2d_context();
 
-                try!(canvas.fetch_all_data().ok_or(Error::InvalidState))
+                canvas.fetch_all_data().ok_or(Error::InvalidState)?
             },
             HTMLImageElementOrHTMLCanvasElementOrCanvasRenderingContext2D::CanvasRenderingContext2D(ref context) => {
                 let canvas = context.Canvas();
                 let _ = canvas.get_or_init_2d_context();
 
-                try!(canvas.fetch_all_data().ok_or(Error::InvalidState))
+                canvas.fetch_all_data().ok_or(Error::InvalidState)?
             }
         };
 
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index f4de73747c4..1be316991da 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -293,11 +293,11 @@ impl DedicatedWorkerGlobalScope {
         }
         let ret = sel.wait();
         if ret == worker_handle.id() {
-            Ok(MixedMessage::FromWorker(try!(worker_port.recv())))
+            Ok(MixedMessage::FromWorker(worker_port.recv()?))
         } else if ret == timer_event_handle.id() {
-            Ok(MixedMessage::FromScheduler(try!(timer_event_port.recv())))
+            Ok(MixedMessage::FromScheduler(timer_event_port.recv()?))
         } else if ret == devtools_handle.id() {
-            Ok(MixedMessage::FromDevtools(try!(devtools_port.recv())))
+            Ok(MixedMessage::FromDevtools(devtools_port.recv()?))
         } else {
             panic!("unexpected select result!")
         }
@@ -384,7 +384,7 @@ impl DedicatedWorkerGlobalScopeMethods for DedicatedWorkerGlobalScope {
     #[allow(unsafe_code)]
     // https://html.spec.whatwg.org/multipage/#dom-dedicatedworkerglobalscope-postmessage
     unsafe fn PostMessage(&self, cx: *mut JSContext, message: HandleValue) -> ErrorResult {
-        let data = try!(StructuredCloneData::write(cx, message));
+        let data = StructuredCloneData::write(cx, message)?;
         let worker = self.worker.borrow().as_ref().unwrap().clone();
         self.parent_sender
             .send(CommonScriptMsg::RunnableMsg(WorkerEvent,
diff --git a/components/script/dom/dissimilaroriginwindow.rs b/components/script/dom/dissimilaroriginwindow.rs
index a4e230e90a2..6a106fab14c 100644
--- a/components/script/dom/dissimilaroriginwindow.rs
+++ b/components/script/dom/dissimilaroriginwindow.rs
@@ -146,7 +146,7 @@ impl DissimilarOriginWindowMethods for DissimilarOriginWindow {
 
         // Step 1-2, 6-8.
         // TODO(#12717): Should implement the `transfer` argument.
-        let data = try!(StructuredCloneData::write(cx, message));
+        let data = StructuredCloneData::write(cx, message)?;
 
         // Step 9.
         self.post_message(origin, data);
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 5db39cf4feb..da3b5db052c 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -1454,7 +1454,7 @@ impl Document {
             for node in nodes {
                 match node {
                     NodeOrString::Node(node) => {
-                        try!(fragment.AppendChild(&node));
+                        fragment.AppendChild(&node)?;
                     },
                     NodeOrString::String(string) => {
                         let node = Root::upcast::<Node>(self.CreateTextNode(string));
@@ -2819,8 +2819,8 @@ impl DocumentMethods for Document {
                        namespace: Option<DOMString>,
                        qualified_name: DOMString)
                        -> Fallible<Root<Element>> {
-        let (namespace, prefix, local_name) = try!(validate_and_extract(namespace,
-                                                                        &qualified_name));
+        let (namespace, prefix, local_name) = validate_and_extract(namespace,
+                                                                        &qualified_name)?;
         let name = QualName::new(prefix, namespace, local_name);
         Ok(Element::create(name, self, ElementCreator::ScriptCreated))
     }
@@ -2845,8 +2845,8 @@ impl DocumentMethods for Document {
                          namespace: Option<DOMString>,
                          qualified_name: DOMString)
                          -> Fallible<Root<Attr>> {
-        let (namespace, prefix, local_name) = try!(validate_and_extract(namespace,
-                                                                        &qualified_name));
+        let (namespace, prefix, local_name) = validate_and_extract(namespace,
+                                                                        &qualified_name)?;
         let value = AttrValue::String("".to_owned());
         let qualified_name = LocalName::from(qualified_name);
         Ok(Attr::new(&self.window,
diff --git a/components/script/dom/domimplementation.rs b/components/script/dom/domimplementation.rs
index e0f9d69a45a..8c1bee4f334 100644
--- a/components/script/dom/domimplementation.rs
+++ b/components/script/dom/domimplementation.rs
@@ -57,7 +57,7 @@ impl DOMImplementationMethods for DOMImplementation {
                           pubid: DOMString,
                           sysid: DOMString)
                           -> Fallible<Root<DocumentType>> {
-        try!(validate_qualified_name(&qualified_name));
+        validate_qualified_name(&qualified_name)?;
         Ok(DocumentType::new(qualified_name, Some(pubid), Some(sysid), &self.document))
     }
 
diff --git a/components/script/dom/domtokenlist.rs b/components/script/dom/domtokenlist.rs
index b07a4357e83..b4be05e2f3b 100644
--- a/components/script/dom/domtokenlist.rs
+++ b/components/script/dom/domtokenlist.rs
@@ -84,7 +84,7 @@ impl DOMTokenListMethods for DOMTokenList {
     fn Add(&self, tokens: Vec<DOMString>) -> ErrorResult {
         let mut atoms = self.element.get_tokenlist_attribute(&self.local_name);
         for token in &tokens {
-            let token = try!(self.check_token_exceptions(&token));
+            let token = self.check_token_exceptions(&token)?;
             if !atoms.iter().any(|atom| *atom == token) {
                 atoms.push(token);
             }
@@ -97,7 +97,7 @@ impl DOMTokenListMethods for DOMTokenList {
     fn Remove(&self, tokens: Vec<DOMString>) -> ErrorResult {
         let mut atoms = self.element.get_tokenlist_attribute(&self.local_name);
         for token in &tokens {
-            let token = try!(self.check_token_exceptions(&token));
+            let token = self.check_token_exceptions(&token)?;
             atoms.iter().position(|atom| *atom == token).map(|index| atoms.remove(index));
         }
         self.element.set_atomic_tokenlist_attribute(&self.local_name, atoms);
@@ -107,7 +107,7 @@ impl DOMTokenListMethods for DOMTokenList {
     // https://dom.spec.whatwg.org/#dom-domtokenlist-toggle
     fn Toggle(&self, token: DOMString, force: Option<bool>) -> Fallible<bool> {
         let mut atoms = self.element.get_tokenlist_attribute(&self.local_name);
-        let token = try!(self.check_token_exceptions(&token));
+        let token = self.check_token_exceptions(&token)?;
         match atoms.iter().position(|atom| *atom == token) {
             Some(index) => match force {
                 Some(true) => Ok(true),
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 7e01bc66764..c0570ad83cc 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -144,9 +144,9 @@ pub struct Element {
 
 impl fmt::Debug for Element {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        try!(write!(f, "<{}", self.local_name));
+        write!(f, "<{}", self.local_name)?;
         if let Some(ref id) = *self.id_attribute.borrow() {
-            try!(write!(f, " id={}", id));
+            write!(f, " id={}", id)?;
         }
         write!(f, ">")
     }
@@ -1532,7 +1532,7 @@ impl ElementMethods for Element {
                       qualified_name: DOMString,
                       value: DOMString) -> ErrorResult {
         let (namespace, prefix, local_name) =
-            try!(validate_and_extract(namespace, &qualified_name));
+            validate_and_extract(namespace, &qualified_name)?;
         let qualified_name = LocalName::from(qualified_name);
         let value = self.parse_attribute(&namespace, &local_name, value);
         self.set_first_matching_attribute(
@@ -1929,7 +1929,7 @@ impl ElementMethods for Element {
     /// https://w3c.github.io/DOM-Parsing/#widl-Element-innerHTML
     fn SetInnerHTML(&self, value: DOMString) -> ErrorResult {
         // Step 1.
-        let frag = try!(self.parse_fragment(value));
+        let frag = self.parse_fragment(value)?;
         // Step 2.
         // https://github.com/w3c/DOM-Parsing/issues/1
         let target = if let Some(template) = self.downcast::<HTMLTemplateElement>() {
@@ -1974,9 +1974,9 @@ impl ElementMethods for Element {
         };
 
         // Step 5.
-        let frag = try!(parent.parse_fragment(value));
+        let frag = parent.parse_fragment(value)?;
         // Step 6.
-        try!(context_parent.ReplaceChild(frag.upcast(), context_node));
+        context_parent.ReplaceChild(frag.upcast(), context_node)?;
         Ok(())
     }
 
@@ -2095,8 +2095,8 @@ impl ElementMethods for Element {
     // https://dom.spec.whatwg.org/#dom-element-insertadjacentelement
     fn InsertAdjacentElement(&self, where_: DOMString, element: &Element)
                              -> Fallible<Option<Root<Element>>> {
-        let where_ = try!(AdjacentPosition::try_from(&*where_));
-        let inserted_node = try!(self.insert_adjacent(where_, element.upcast()));
+        let where_ = AdjacentPosition::try_from(&*where_)?;
+        let inserted_node = self.insert_adjacent(where_, element.upcast())?;
         Ok(inserted_node.map(|node| Root::downcast(node).unwrap()))
     }
 
@@ -2107,7 +2107,7 @@ impl ElementMethods for Element {
         let text = Text::new(data, &document_from_node(self));
 
         // Step 2.
-        let where_ = try!(AdjacentPosition::try_from(&*where_));
+        let where_ = AdjacentPosition::try_from(&*where_)?;
         self.insert_adjacent(where_, text.upcast()).map(|_| ())
     }
 
@@ -2115,7 +2115,7 @@ impl ElementMethods for Element {
     fn InsertAdjacentHTML(&self, position: DOMString, text: DOMString)
                           -> ErrorResult {
         // Step 1.
-        let position = try!(AdjacentPosition::try_from(&*position));
+        let position = AdjacentPosition::try_from(&*position)?;
 
         let context = match position {
             AdjacentPosition::BeforeBegin | AdjacentPosition::AfterEnd => {
@@ -2137,7 +2137,7 @@ impl ElementMethods for Element {
             &context.owner_doc(), context.downcast::<Element>());
 
         // Step 3.
-        let fragment = try!(context.parse_fragment(text));
+        let fragment = context.parse_fragment(text)?;
 
         // Step 4.
         self.insert_adjacent(position, fragment.upcast()).map(|_| ())
diff --git a/components/script/dom/headers.rs b/components/script/dom/headers.rs
index 728588533a4..516100d6edc 100644
--- a/components/script/dom/headers.rs
+++ b/components/script/dom/headers.rs
@@ -52,7 +52,7 @@ impl Headers {
     pub fn Constructor(global: &GlobalScope, init: Option<HeadersInit>)
                        -> Fallible<Root<Headers>> {
         let dom_headers_new = Headers::new(global);
-        try!(dom_headers_new.fill(init));
+        dom_headers_new.fill(init)?;
         Ok(dom_headers_new)
     }
 }
@@ -63,7 +63,7 @@ impl HeadersMethods for Headers {
         // Step 1
         let value = normalize_value(value);
         // Step 2
-        let (mut valid_name, valid_value) = try!(validate_name_and_value(name, value));
+        let (mut valid_name, valid_value) = validate_name_and_value(name, value)?;
         valid_name = valid_name.to_lowercase();
         // Step 3
         if self.guard.get() == Guard::Immutable {
@@ -95,7 +95,7 @@ impl HeadersMethods for Headers {
     // https://fetch.spec.whatwg.org/#dom-headers-delete
     fn Delete(&self, name: ByteString) -> ErrorResult {
         // Step 1
-        let valid_name = try!(validate_name(name));
+        let valid_name = validate_name(name)?;
         // Step 2
         if self.guard.get() == Guard::Immutable {
             return Err(Error::Type("Guard is immutable".to_string()));
@@ -121,7 +121,7 @@ impl HeadersMethods for Headers {
     // https://fetch.spec.whatwg.org/#dom-headers-get
     fn Get(&self, name: ByteString) -> Fallible<Option<ByteString>> {
         // Step 1
-        let valid_name = &try!(validate_name(name));
+        let valid_name = &validate_name(name)?;
         Ok(self.header_list.borrow().get_raw(&valid_name).map(|v| {
             ByteString::new(v[0].clone())
         }))
@@ -130,7 +130,7 @@ impl HeadersMethods for Headers {
     // https://fetch.spec.whatwg.org/#dom-headers-has
     fn Has(&self, name: ByteString) -> Fallible<bool> {
         // Step 1
-        let valid_name = try!(validate_name(name));
+        let valid_name = validate_name(name)?;
         // Step 2
         Ok(self.header_list.borrow_mut().get_raw(&valid_name).is_some())
     }
@@ -140,7 +140,7 @@ impl HeadersMethods for Headers {
         // Step 1
         let value = normalize_value(value);
         // Step 2
-        let (mut valid_name, valid_value) = try!(validate_name_and_value(name, value));
+        let (mut valid_name, valid_value) = validate_name_and_value(name, value)?;
         valid_name = valid_name.to_lowercase();
         // Step 3
         if self.guard.get() == Guard::Immutable {
@@ -172,10 +172,10 @@ impl Headers {
             // Step 1
             Some(HeadersInit::Headers(h)) => {
                 for header in h.header_list.borrow().iter() {
-                    try!(self.Append(
+                    self.Append(
                         ByteString::new(Vec::from(header.name())),
                         ByteString::new(Vec::from(header.value_string().into_bytes()))
-                    ));
+                    )?;
                 }
                 Ok(())
             },
@@ -185,7 +185,7 @@ impl Headers {
                     if seq.len() == 2 {
                         let val = seq.pop().unwrap();
                         let name = seq.pop().unwrap();
-                        try!(self.Append(name, val));
+                        self.Append(name, val)?;
                     } else {
                         return Err(Error::Type(
                             format!("Each header object must be a sequence of length 2 - found one with length {}",
@@ -198,7 +198,7 @@ impl Headers {
                 for (key, value) in m.iter() {
                     let key_vec = key.as_ref().to_string().into();
                     let headers_key = ByteString::new(key_vec);
-                    try!(self.Append(headers_key, value.clone()));
+                    self.Append(headers_key, value.clone())?;
                 }
                 Ok(())
             },
@@ -360,7 +360,7 @@ pub fn is_forbidden_header_name(name: &str) -> bool {
 // [4] https://www.rfc-editor.org/errata_search.php?rfc=7230
 fn validate_name_and_value(name: ByteString, value: ByteString)
                            -> Fallible<(String, Vec<u8>)> {
-    let valid_name = try!(validate_name(name));
+    let valid_name = validate_name(name)?;
     if !is_field_content(&value) {
         return Err(Error::Type("Value is not valid".to_string()));
     }
diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 2454b634040..a95ff766171 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -297,9 +297,9 @@ impl HTMLCanvasElementMethods for HTMLCanvasElement {
         // Step 3.
         let raw_data = match *self.context.borrow() {
             Some(CanvasContext::Context2d(ref context)) => {
-                let image_data = try!(context.GetImageData(Finite::wrap(0f64), Finite::wrap(0f64),
+                let image_data = context.GetImageData(Finite::wrap(0f64), Finite::wrap(0f64),
                                                            Finite::wrap(self.Width() as f64),
-                                                           Finite::wrap(self.Height() as f64)));
+                                                           Finite::wrap(self.Height() as f64))?;
                 image_data.get_data_array()
             }
             None => {
diff --git a/components/script/dom/htmloptionscollection.rs b/components/script/dom/htmloptionscollection.rs
index 42d6aebde35..f3b839a8a2a 100644
--- a/components/script/dom/htmloptionscollection.rs
+++ b/components/script/dom/htmloptionscollection.rs
@@ -49,7 +49,7 @@ impl HTMLOptionsCollection {
         for _ in 0..count {
             let element = HTMLOptionElement::new(local_name!("option"), None, &document);
             let node = element.upcast::<Node>();
-            try!(root.AppendChild(node));
+            root.AppendChild(node)?;
         };
         Ok(())
     }
@@ -90,7 +90,7 @@ impl HTMLOptionsCollectionMethods for HTMLOptionsCollection {
 
             // Step 4
             if n > 0 {
-                try!(self.add_new_elements(n as u32));
+                self.add_new_elements(n as u32)?;
             }
 
             // Step 5
diff --git a/components/script/dom/htmltableelement.rs b/components/script/dom/htmltableelement.rs
index 3e0310dad9a..7f3d9974a74 100644
--- a/components/script/dom/htmltableelement.rs
+++ b/components/script/dom/htmltableelement.rs
@@ -103,7 +103,7 @@ impl HTMLTableElement {
             let reference_element = node.child_elements().find(reference_predicate);
             let reference_node = reference_element.r().map(|e| e.upcast());
 
-            try!(node.InsertBefore(section.upcast(), reference_node));
+            node.InsertBefore(section.upcast(), reference_node)?;
         }
 
         Ok(())
diff --git a/components/script/dom/imagedata.rs b/components/script/dom/imagedata.rs
index a8a5e1ed4e7..70f6d8ea992 100644
--- a/components/script/dom/imagedata.rs
+++ b/components/script/dom/imagedata.rs
@@ -65,8 +65,8 @@ impl ImageData {
         if let Some(jsobject) = opt_jsobject {
             let cx = global.get_cx();
             typedarray!(in(cx) let array_res: Uint8ClampedArray = jsobject);
-            let mut array = try!(array_res
-                .map_err(|_| Error::Type("Argument to Image data is not an Uint8ClampedArray".to_owned())));
+            let mut array = array_res
+                .map_err(|_| Error::Type("Argument to Image data is not an Uint8ClampedArray".to_owned()))?;
 
             let byte_len = array.as_slice().len() as u32;
             if byte_len % 4 != 0 {
diff --git a/components/script/dom/location.rs b/components/script/dom/location.rs
index cac2322be82..c725e6cee54 100644
--- a/components/script/dom/location.rs
+++ b/components/script/dom/location.rs
@@ -70,7 +70,7 @@ impl Location {
 impl LocationMethods for Location {
     // https://html.spec.whatwg.org/multipage/#dom-location-assign
     fn Assign(&self, url: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         // TODO: per spec, we should use the _API base URL_ specified by the
         //       _entry settings object_.
         let base_url = self.window.get_url();
@@ -84,7 +84,7 @@ impl LocationMethods for Location {
 
     // https://html.spec.whatwg.org/multipage/#dom-location-reload
     fn Reload(&self) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.window.load_url(self.get_url(), true, true, None);
         Ok(())
     }
@@ -105,7 +105,7 @@ impl LocationMethods for Location {
 
     // https://html.spec.whatwg.org/multipage/#dom-location-hash
     fn GetHash(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Hash(&self.get_url()))
     }
 
@@ -114,46 +114,46 @@ impl LocationMethods for Location {
         if value.0.is_empty() {
             value = USVString("#".to_owned());
         }
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetHash);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-host
     fn GetHost(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Host(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-host
     fn SetHost(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetHost);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-origin
     fn GetOrigin(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Origin(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-hostname
     fn GetHostname(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Hostname(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-hostname
     fn SetHostname(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetHostname);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-href
     fn GetHref(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Href(&self.get_url()))
     }
 
@@ -170,57 +170,57 @@ impl LocationMethods for Location {
 
     // https://html.spec.whatwg.org/multipage/#dom-location-pathname
     fn GetPathname(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Pathname(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-pathname
     fn SetPathname(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetPathname);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-port
     fn GetPort(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Port(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-port
     fn SetPort(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetPort);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-protocol
     fn GetProtocol(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Protocol(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-protocol
     fn SetProtocol(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetProtocol);
         Ok(())
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-href
     fn Stringifier(&self) -> Fallible<DOMString> {
-        Ok(DOMString::from(try!(self.GetHref()).0))
+        Ok(DOMString::from(self.GetHref()?.0))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-search
     fn GetSearch(&self) -> Fallible<USVString> {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         Ok(UrlHelper::Search(&self.get_url()))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location-search
     fn SetSearch(&self, value: USVString) -> ErrorResult {
-        try!(self.check_same_origin_domain());
+        self.check_same_origin_domain()?;
         self.set_url_component(value, UrlHelper::SetSearch);
         Ok(())
     }
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 88ad070bba7..cace0497433 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -631,7 +631,7 @@ impl Node {
         let viable_previous_sibling = first_node_not_in(self.preceding_siblings(), &nodes);
 
         // Step 4.
-        let node = try!(self.owner_doc().node_from_nodes_and_strings(nodes));
+        let node = self.owner_doc().node_from_nodes_and_strings(nodes)?;
 
         // Step 5.
         let viable_previous_sibling = match viable_previous_sibling {
@@ -640,7 +640,7 @@ impl Node {
         };
 
         // Step 6.
-        try!(Node::pre_insert(&node, &parent, viable_previous_sibling.r()));
+        Node::pre_insert(&node, &parent, viable_previous_sibling.r())?;
 
         Ok(())
     }
@@ -660,10 +660,10 @@ impl Node {
         let viable_next_sibling = first_node_not_in(self.following_siblings(), &nodes);
 
         // Step 4.
-        let node = try!(self.owner_doc().node_from_nodes_and_strings(nodes));
+        let node = self.owner_doc().node_from_nodes_and_strings(nodes)?;
 
         // Step 5.
-        try!(Node::pre_insert(&node, &parent, viable_next_sibling.r()));
+        Node::pre_insert(&node, &parent, viable_next_sibling.r())?;
 
         Ok(())
     }
@@ -680,13 +680,13 @@ impl Node {
         // Step 3.
         let viable_next_sibling = first_node_not_in(self.following_siblings(), &nodes);
         // Step 4.
-        let node = try!(self.owner_doc().node_from_nodes_and_strings(nodes));
+        let node = self.owner_doc().node_from_nodes_and_strings(nodes)?;
         if self.parent_node == Some(&*parent) {
             // Step 5.
-            try!(parent.ReplaceChild(&node, self));
+            parent.ReplaceChild(&node, self)?;
         } else {
             // Step 6.
-            try!(Node::pre_insert(&node, &parent, viable_next_sibling.r()));
+            Node::pre_insert(&node, &parent, viable_next_sibling.r())?;
         }
         Ok(())
     }
@@ -695,7 +695,7 @@ impl Node {
     pub fn prepend(&self, nodes: Vec<NodeOrString>) -> ErrorResult {
         // Step 1.
         let doc = self.owner_doc();
-        let node = try!(doc.node_from_nodes_and_strings(nodes));
+        let node = doc.node_from_nodes_and_strings(nodes)?;
         // Step 2.
         let first_child = self.first_child.get();
         Node::pre_insert(&node, self, first_child.r()).map(|_| ())
@@ -705,7 +705,7 @@ impl Node {
     pub fn append(&self, nodes: Vec<NodeOrString>) -> ErrorResult {
         // Step 1.
         let doc = self.owner_doc();
-        let node = try!(doc.node_from_nodes_and_strings(nodes));
+        let node = doc.node_from_nodes_and_strings(nodes)?;
         // Step 2.
         self.AppendChild(&node).map(|_| ())
     }
@@ -751,7 +751,7 @@ impl Node {
     #[allow(unsafe_code)]
     pub fn query_selector_all(&self, selectors: DOMString) -> Fallible<Root<NodeList>> {
         let window = window_from_node(self);
-        let iter = try!(self.query_selector_iter(selectors));
+        let iter = self.query_selector_iter(selectors)?;
         Ok(NodeList::new_simple_list(&window, iter))
     }
 
@@ -852,7 +852,7 @@ impl Node {
         {
             let tr_node = tr.upcast::<Node>();
             if index == -1 {
-                try!(self.InsertBefore(tr_node, None));
+                self.InsertBefore(tr_node, None)?;
             } else {
                 let items = get_items();
                 let node = match items.elements_iter()
@@ -863,7 +863,7 @@ impl Node {
                     None => return Err(Error::IndexSize),
                     Some(node) => node,
                 };
-                try!(self.InsertBefore(tr_node, node.r()));
+                self.InsertBefore(tr_node, node.r())?;
             }
         }
 
@@ -1566,7 +1566,7 @@ impl Node {
     pub fn pre_insert(node: &Node, parent: &Node, child: Option<&Node>)
                       -> Fallible<Root<Node>> {
         // Step 1.
-        try!(Node::ensure_pre_insertion_validity(node, parent, child));
+        Node::ensure_pre_insertion_validity(node, parent, child)?;
 
         // Steps 2-3.
         let reference_child_root;
diff --git a/components/script/dom/nodeiterator.rs b/components/script/dom/nodeiterator.rs
index 91b590a3647..93e50ca46a9 100644
--- a/components/script/dom/nodeiterator.rs
+++ b/components/script/dom/nodeiterator.rs
@@ -107,7 +107,7 @@ impl NodeIteratorMethods for NodeIterator {
             before_node = false;
 
             // Step 3-2.
-            let result = try!(self.accept_node(&node));
+            let result = self.accept_node(&node)?;
 
             // Step 3-3.
             if result == NodeFilterConstants::FILTER_ACCEPT {
@@ -122,7 +122,7 @@ impl NodeIteratorMethods for NodeIterator {
         // Step 3-1.
         for following_node in node.following_nodes(&self.root_node) {
             // Step 3-2.
-            let result = try!(self.accept_node(&following_node));
+            let result = self.accept_node(&following_node)?;
 
             // Step 3-3.
             if result == NodeFilterConstants::FILTER_ACCEPT {
@@ -151,7 +151,7 @@ impl NodeIteratorMethods for NodeIterator {
             before_node = true;
 
             // Step 3-2.
-            let result = try!(self.accept_node(&node));
+            let result = self.accept_node(&node)?;
 
             // Step 3-3.
             if result == NodeFilterConstants::FILTER_ACCEPT {
@@ -166,7 +166,7 @@ impl NodeIteratorMethods for NodeIterator {
         // Step 3-1.
         for preceding_node in node.preceding_nodes(&self.root_node) {
             // Step 3-2.
-            let result = try!(self.accept_node(&preceding_node));
+            let result = self.accept_node(&preceding_node)?;
 
             // Step 3-3.
             if result == NodeFilterConstants::FILTER_ACCEPT {
diff --git a/components/script/dom/range.rs b/components/script/dom/range.rs
index b5521e93d55..fa849a0fc1a 100644
--- a/components/script/dom/range.rs
+++ b/components/script/dom/range.rs
@@ -269,25 +269,25 @@ impl RangeMethods for Range {
 
     // https://dom.spec.whatwg.org/#dom-range-setstartbefore
     fn SetStartBefore(&self, node: &Node) -> ErrorResult {
-        let parent = try!(node.GetParentNode().ok_or(Error::InvalidNodeType));
+        let parent = node.GetParentNode().ok_or(Error::InvalidNodeType)?;
         self.SetStart(&parent, node.index())
     }
 
     // https://dom.spec.whatwg.org/#dom-range-setstartafter
     fn SetStartAfter(&self, node: &Node) -> ErrorResult {
-        let parent = try!(node.GetParentNode().ok_or(Error::InvalidNodeType));
+        let parent = node.GetParentNode().ok_or(Error::InvalidNodeType)?;
         self.SetStart(&parent, node.index() + 1)
     }
 
     // https://dom.spec.whatwg.org/#dom-range-setendbefore
     fn SetEndBefore(&self, node: &Node) -> ErrorResult {
-        let parent = try!(node.GetParentNode().ok_or(Error::InvalidNodeType));
+        let parent = node.GetParentNode().ok_or(Error::InvalidNodeType)?;
         self.SetEnd(&parent, node.index())
     }
 
     // https://dom.spec.whatwg.org/#dom-range-setendafter
     fn SetEndAfter(&self, node: &Node) -> ErrorResult {
-        let parent = try!(node.GetParentNode().ok_or(Error::InvalidNodeType));
+        let parent = node.GetParentNode().ok_or(Error::InvalidNodeType)?;
         self.SetEnd(&parent, node.index() + 1)
     }
 
@@ -303,7 +303,7 @@ impl RangeMethods for Range {
     // https://dom.spec.whatwg.org/#dom-range-selectnode
     fn SelectNode(&self, node: &Node) -> ErrorResult {
         // Steps 1, 2.
-        let parent = try!(node.GetParentNode().ok_or(Error::InvalidNodeType));
+        let parent = node.GetParentNode().ok_or(Error::InvalidNodeType)?;
         // Step 3.
         let index = node.index();
         // Step 4.
@@ -446,7 +446,7 @@ impl RangeMethods for Range {
                 let data = cdata.SubstringData(start_offset, end_offset - start_offset).unwrap();
                 let clone = cdata.clone_with_data(data, &start_node.owner_doc());
                 // Step 4.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 4.4
                 return Ok(fragment);
             }
@@ -454,7 +454,7 @@ impl RangeMethods for Range {
 
         // Steps 5-12.
         let (first_contained_child, last_contained_child, contained_children) =
-            try!(self.contained_children());
+            self.contained_children()?;
 
         if let Some(child) = first_contained_child {
             // Step 13.
@@ -464,12 +464,12 @@ impl RangeMethods for Range {
                 let data = cdata.SubstringData(start_offset, start_node.len() - start_offset).unwrap();
                 let clone = cdata.clone_with_data(data, &start_node.owner_doc());
                 // Step 13.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
             } else {
                 // Step 14.1.
                 let clone = child.CloneNode(false);
                 // Step 14.2.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 14.3.
                 let subrange = Range::new(&clone.owner_doc(),
                                           &start_node,
@@ -477,9 +477,9 @@ impl RangeMethods for Range {
                                           &child,
                                           child.len());
                 // Step 14.4.
-                let subfragment = try!(subrange.CloneContents());
+                let subfragment = subrange.CloneContents()?;
                 // Step 14.5.
-                try!(clone.AppendChild(subfragment.upcast()));
+                clone.AppendChild(subfragment.upcast())?;
             }
         }
 
@@ -488,7 +488,7 @@ impl RangeMethods for Range {
             // Step 15.1.
             let clone = child.CloneNode(true);
             // Step 15.2.
-            try!(fragment.upcast::<Node>().AppendChild(&clone));
+            fragment.upcast::<Node>().AppendChild(&clone)?;
         }
 
         if let Some(child) = last_contained_child {
@@ -499,12 +499,12 @@ impl RangeMethods for Range {
                 let data = cdata.SubstringData(0, end_offset).unwrap();
                 let clone = cdata.clone_with_data(data, &start_node.owner_doc());
                 // Step 16.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
             } else {
                 // Step 17.1.
                 let clone = child.CloneNode(false);
                 // Step 17.2.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 17.3.
                 let subrange = Range::new(&clone.owner_doc(),
                                           &child,
@@ -512,9 +512,9 @@ impl RangeMethods for Range {
                                           &end_node,
                                           end_offset);
                 // Step 17.4.
-                let subfragment = try!(subrange.CloneContents());
+                let subfragment = subrange.CloneContents()?;
                 // Step 17.5.
-                try!(clone.AppendChild(subfragment.upcast()));
+                clone.AppendChild(subfragment.upcast())?;
             }
         }
 
@@ -547,11 +547,11 @@ impl RangeMethods for Range {
                 let text = end_data.SubstringData(start_offset, end_offset - start_offset);
                 clone.downcast::<CharacterData>().unwrap().SetData(text.unwrap());
                 // Step 4.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 4.4.
-                try!(end_data.ReplaceData(start_offset,
+                end_data.ReplaceData(start_offset,
                                           end_offset - start_offset,
-                                          DOMString::new()));
+                                          DOMString::new())?;
                 // Step 4.5.
                 return Ok(fragment);
             }
@@ -559,7 +559,7 @@ impl RangeMethods for Range {
 
         // Steps 5-12.
         let (first_contained_child, last_contained_child, contained_children) =
-            try!(self.contained_children());
+            self.contained_children()?;
 
         let (new_node, new_offset) = if start_node.is_inclusive_ancestor_of(&end_node) {
             // Step 13.
@@ -584,16 +584,16 @@ impl RangeMethods for Range {
                                                     start_node.len() - start_offset);
                 clone.downcast::<CharacterData>().unwrap().SetData(text.unwrap());
                 // Step 15.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 15.4.
-                try!(start_data.ReplaceData(start_offset,
+                start_data.ReplaceData(start_offset,
                                             start_node.len() - start_offset,
-                                            DOMString::new()));
+                                            DOMString::new())?;
             } else {
                 // Step 16.1.
                 let clone = child.CloneNode(false);
                 // Step 16.2.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 16.3.
                 let subrange = Range::new(&clone.owner_doc(),
                                           &start_node,
@@ -601,15 +601,15 @@ impl RangeMethods for Range {
                                           &child,
                                           child.len());
                 // Step 16.4.
-                let subfragment = try!(subrange.ExtractContents());
+                let subfragment = subrange.ExtractContents()?;
                 // Step 16.5.
-                try!(clone.AppendChild(subfragment.upcast()));
+                clone.AppendChild(subfragment.upcast())?;
             }
         }
 
         // Step 17.
         for child in contained_children {
-            try!(fragment.upcast::<Node>().AppendChild(&child));
+            fragment.upcast::<Node>().AppendChild(&child)?;
         }
 
         if let Some(child) = last_contained_child {
@@ -621,14 +621,14 @@ impl RangeMethods for Range {
                 let text = end_data.SubstringData(0, end_offset);
                 clone.downcast::<CharacterData>().unwrap().SetData(text.unwrap());
                 // Step 18.3.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 18.4.
-                try!(end_data.ReplaceData(0, end_offset, DOMString::new()));
+                end_data.ReplaceData(0, end_offset, DOMString::new())?;
             } else {
                 // Step 19.1.
                 let clone = child.CloneNode(false);
                 // Step 19.2.
-                try!(fragment.upcast::<Node>().AppendChild(&clone));
+                fragment.upcast::<Node>().AppendChild(&clone)?;
                 // Step 19.3.
                 let subrange = Range::new(&clone.owner_doc(),
                                           &child,
@@ -636,15 +636,15 @@ impl RangeMethods for Range {
                                           &end_node,
                                           end_offset);
                 // Step 19.4.
-                let subfragment = try!(subrange.ExtractContents());
+                let subfragment = subrange.ExtractContents()?;
                 // Step 19.5.
-                try!(clone.AppendChild(subfragment.upcast()));
+                clone.AppendChild(subfragment.upcast())?;
             }
         }
 
         // Step 20.
-        try!(self.SetStart(&new_node, new_offset));
-        try!(self.SetEnd(&new_node, new_offset));
+        self.SetStart(&new_node, new_offset)?;
+        self.SetEnd(&new_node, new_offset)?;
 
         // Step 21.
         Ok(fragment)
@@ -690,16 +690,16 @@ impl RangeMethods for Range {
             };
 
         // Step 6.
-        try!(Node::ensure_pre_insertion_validity(node,
+        Node::ensure_pre_insertion_validity(node,
                                                  &parent,
-                                                 reference_node.r()));
+                                                 reference_node.r())?;
 
         // Step 7.
         let split_text;
         let reference_node =
             match start_node.downcast::<Text>() {
                 Some(text) => {
-                    split_text = try!(text.SplitText(start_offset));
+                    split_text = text.SplitText(start_offset)?;
                     let new_reference = Root::upcast::<Node>(split_text);
                     assert!(new_reference.GetParentNode().r() == Some(&parent));
                     Some(new_reference)
@@ -729,7 +729,7 @@ impl RangeMethods for Range {
         };
 
         // Step 12.
-        try!(Node::pre_insert(node, &parent, reference_node.r()));
+        Node::pre_insert(node, &parent, reference_node.r())?;
 
         // Step 13.
         if self.Collapsed() {
@@ -839,16 +839,16 @@ impl RangeMethods for Range {
         }
 
         // Step 3.
-        let fragment = try!(self.ExtractContents());
+        let fragment = self.ExtractContents()?;
 
         // Step 4.
         Node::replace_all(None, new_parent);
 
         // Step 5.
-        try!(self.InsertNode(new_parent));
+        self.InsertNode(new_parent)?;
 
         // Step 6.
-        try!(new_parent.AppendChild(fragment.upcast()));
+        new_parent.AppendChild(fragment.upcast())?;
 
         // Step 7.
         self.SelectNode(new_parent)
@@ -915,7 +915,7 @@ impl RangeMethods for Range {
         let element = Element::fragment_parsing_context(&owner_doc, element.r());
 
         // Step 3.
-        let fragment_node = try!(element.parse_fragment(fragment));
+        let fragment_node = element.parse_fragment(fragment)?;
 
         // Step 4.
         for node in fragment_node.upcast::<Node>().traverse_preorder() {
diff --git a/components/script/dom/request.rs b/components/script/dom/request.rs
index 65882c1b4ed..5894eae8de7 100644
--- a/components/script/dom/request.rs
+++ b/components/script/dom/request.rs
@@ -308,12 +308,12 @@ impl Request {
                     headers_copy = Root::from_ref(&*init_headers);
                 }
                 &HeadersInit::ByteStringSequenceSequence(ref init_sequence) => {
-                    try!(headers_copy.fill(Some(
-                        HeadersInit::ByteStringSequenceSequence(init_sequence.clone()))));
+                    headers_copy.fill(Some(
+                        HeadersInit::ByteStringSequenceSequence(init_sequence.clone())))?;
                 },
                 &HeadersInit::StringByteStringRecord(ref init_map) => {
-                    try!(headers_copy.fill(Some(
-                        HeadersInit::StringByteStringRecord(init_map.clone()))));
+                    headers_copy.fill(Some(
+                        HeadersInit::StringByteStringRecord(init_map.clone())))?;
                 },
             }
         }
@@ -351,10 +351,10 @@ impl Request {
                 // but an input with headers is given, set request's
                 // headers as the input's Headers.
                 if let RequestInfo::Request(ref input_request) = input {
-                    try!(r.Headers().fill(Some(HeadersInit::Headers(input_request.Headers()))));
+                    r.Headers().fill(Some(HeadersInit::Headers(input_request.Headers())))?;
                 }
             },
-            Some(HeadersInit::Headers(_)) => try!(r.Headers().fill(Some(HeadersInit::Headers(headers_copy)))),
+            Some(HeadersInit::Headers(_)) => r.Headers().fill(Some(HeadersInit::Headers(headers_copy)))?,
             _ => {},
         }
 
@@ -391,8 +391,8 @@ impl Request {
             // Step 34.3
             if let Some(contents) = content_type {
                 if !r.Headers().Has(ByteString::new(b"Content-Type".to_vec())).unwrap() {
-                    try!(r.Headers().Append(ByteString::new(b"Content-Type".to_vec()),
-                                            ByteString::new(contents.as_bytes().to_vec())));
+                    r.Headers().Append(ByteString::new(b"Content-Type".to_vec()),
+                                            ByteString::new(contents.as_bytes().to_vec()))?;
                 }
             }
         }
@@ -446,7 +446,7 @@ impl Request {
         *r_clone.request.borrow_mut() = req.clone();
         r_clone.body_used.set(body_used);
         *r_clone.mime_type.borrow_mut() = mime_type;
-        try!(r_clone.Headers().fill(Some(HeadersInit::Headers(r.Headers()))));
+        r_clone.Headers().fill(Some(HeadersInit::Headers(r.Headers())))?;
         r_clone.Headers().set_guard(headers_guard);
         Ok(r_clone)
     }
diff --git a/components/script/dom/response.rs b/components/script/dom/response.rs
index 089a8acca6c..c2b2dd20346 100644
--- a/components/script/dom/response.rs
+++ b/components/script/dom/response.rs
@@ -101,7 +101,7 @@ impl Response {
             r.Headers().empty_header_list();
 
             // Step 6.2
-            try!(r.Headers().fill(Some(headers_member.clone())));
+            r.Headers().fill(Some(headers_member.clone()))?;
         }
 
         // Step 7
@@ -119,8 +119,8 @@ impl Response {
             // Step 7.4
             if let Some(content_type_contents) = content_type {
                 if !r.Headers().Has(ByteString::new(b"Content-Type".to_vec())).unwrap() {
-                    try!(r.Headers().Append(ByteString::new(b"Content-Type".to_vec()),
-                                            ByteString::new(content_type_contents.as_bytes().to_vec())));
+                    r.Headers().Append(ByteString::new(b"Content-Type".to_vec()),
+                                            ByteString::new(content_type_contents.as_bytes().to_vec()))?;
                 }
             };
         }
@@ -174,7 +174,7 @@ impl Response {
 
         // Step 6
         let url_bytestring = ByteString::from_str(url.as_str()).unwrap_or(ByteString::new(b"".to_vec()));
-        try!(r.Headers().Set(ByteString::new(b"Location".to_vec()), url_bytestring));
+        r.Headers().Set(ByteString::new(b"Location".to_vec()), url_bytestring)?;
 
         // Step 4 continued
         // Headers Guard is set to Immutable here to prevent error in Step 6
@@ -305,7 +305,7 @@ impl ResponseMethods for Response {
         // Step 2
         let new_response = Response::new(&self.global());
         new_response.Headers().set_guard(self.Headers().get_guard());
-        try!(new_response.Headers().fill(Some(HeadersInit::Headers(self.Headers()))));
+        new_response.Headers().fill(Some(HeadersInit::Headers(self.Headers())))?;
 
         // https://fetch.spec.whatwg.org/#concept-response-clone
         // Instead of storing a net_traits::Response internally, we
diff --git a/components/script/dom/serviceworker.rs b/components/script/dom/serviceworker.rs
index b59c1da1afc..7e17a9040e7 100644
--- a/components/script/dom/serviceworker.rs
+++ b/components/script/dom/serviceworker.rs
@@ -89,7 +89,7 @@ impl ServiceWorkerMethods for ServiceWorker {
             return Err(Error::InvalidState);
         }
         // Step 7
-        let data = try!(StructuredCloneData::write(cx, message));
+        let data = StructuredCloneData::write(cx, message)?;
         let msg_vec = DOMMessage(data.move_to_arraybuffer());
         let _ =
             self.global()
diff --git a/components/script/dom/serviceworkerglobalscope.rs b/components/script/dom/serviceworkerglobalscope.rs
index 953a6ae8328..ebcc34aac0e 100644
--- a/components/script/dom/serviceworkerglobalscope.rs
+++ b/components/script/dom/serviceworkerglobalscope.rs
@@ -303,11 +303,11 @@ impl ServiceWorkerGlobalScope {
 
         let ret = sel.wait();
         if ret == worker_handle.id() {
-            Ok(MixedMessage::FromServiceWorker(try!(worker_port.recv())))
+            Ok(MixedMessage::FromServiceWorker(worker_port.recv()?))
         }else if ret == devtools_handle.id() {
-            Ok(MixedMessage::FromDevtools(try!(devtools_port.recv())))
+            Ok(MixedMessage::FromDevtools(devtools_port.recv()?))
         } else if ret == timer_port_handle.id() {
-            Ok(MixedMessage::FromTimeoutThread(try!(timer_event_port.recv())))
+            Ok(MixedMessage::FromTimeoutThread(timer_event_port.recv()?))
         } else {
             panic!("unexpected select result!")
         }
diff --git a/components/script/dom/servoparser/html.rs b/components/script/dom/servoparser/html.rs
index 2f0bdd8f7f1..6d8f894a074 100644
--- a/components/script/dom/servoparser/html.rs
+++ b/components/script/dom/servoparser/html.rs
@@ -135,7 +135,7 @@ impl<'a> Serialize for &'a Node {
                         let ar: AttrRef = (&qname, &**value);
                         ar
                     });
-                    try!(serializer.start_elem(name.clone(), attr_refs));
+                    serializer.start_elem(name.clone(), attr_refs)?;
                 }
 
                 let children = if let Some(tpl) = node.downcast::<HTMLTemplateElement>() {
@@ -146,18 +146,18 @@ impl<'a> Serialize for &'a Node {
                 };
 
                 for handle in children {
-                    try!((&*handle).serialize(serializer, IncludeNode));
+                    (&*handle).serialize(serializer, IncludeNode)?;
                 }
 
                 if traversal_scope == IncludeNode {
-                    try!(serializer.end_elem(name.clone()));
+                    serializer.end_elem(name.clone())?;
                 }
                 Ok(())
             },
 
             (ChildrenOnly, NodeTypeId::Document(_)) => {
                 for handle in node.children() {
-                    try!((&*handle).serialize(serializer, IncludeNode));
+                    (&*handle).serialize(serializer, IncludeNode)?;
                 }
                 Ok(())
             },
diff --git a/components/script/dom/treewalker.rs b/components/script/dom/treewalker.rs
index 2409d65af4f..8515d7b6ae7 100644
--- a/components/script/dom/treewalker.rs
+++ b/components/script/dom/treewalker.rs
@@ -104,7 +104,7 @@ impl TreeWalkerMethods for TreeWalker {
                     node = n;
                     // "2. If node is not null and filtering node returns FILTER_ACCEPT,
                     //     then set the currentNode attribute to node, return node."
-                    if NodeFilterConstants::FILTER_ACCEPT == try!(self.accept_node(&node)) {
+                    if NodeFilterConstants::FILTER_ACCEPT == self.accept_node(&node)? {
                         self.current_node.set(&node);
                         return Ok(Some(node))
                     }
@@ -163,7 +163,7 @@ impl TreeWalkerMethods for TreeWalker {
                 // "4. If result is FILTER_ACCEPT, then
                 //     set the currentNode attribute to node and return node."
                 loop {
-                    let result = try!(self.accept_node(&node));
+                    let result = self.accept_node(&node)?;
                     match result {
                         NodeFilterConstants::FILTER_REJECT => break,
                         _ if node.GetFirstChild().is_some() =>
@@ -192,7 +192,7 @@ impl TreeWalkerMethods for TreeWalker {
             }
             // "5. Filter node and if the return value is FILTER_ACCEPT, then
             //     set the currentNode attribute to node and return node."
-            if NodeFilterConstants::FILTER_ACCEPT == try!(self.accept_node(&node)) {
+            if NodeFilterConstants::FILTER_ACCEPT == self.accept_node(&node)? {
                 self.current_node.set(&node);
                 return Ok(Some(node))
             }
@@ -220,7 +220,7 @@ impl TreeWalkerMethods for TreeWalker {
                         // "1. Set node to its first child."
                         node = child;
                         // "2. Filter node and set result to the return value."
-                        result = try!(self.accept_node(&node));
+                        result = self.accept_node(&node)?;
                         // "3. If result is FILTER_ACCEPT, then
                         //     set the currentNode attribute to node and return node."
                         if NodeFilterConstants::FILTER_ACCEPT == result {
@@ -238,7 +238,7 @@ impl TreeWalkerMethods for TreeWalker {
                 Some(n) => {
                     node = n;
                     // "3. Filter node and set result to the return value."
-                    result = try!(self.accept_node(&node));
+                    result = self.accept_node(&node)?;
                     // "4. If result is FILTER_ACCEPT, then
                     //     set the currentNode attribute to node and return node."
                     if NodeFilterConstants::FILTER_ACCEPT == result {
@@ -275,7 +275,7 @@ impl TreeWalker {
         // 4. Main: Repeat these substeps:
         'main: loop {
             // "1. Filter node and let result be the return value."
-            let result = try!(self.accept_node(&node));
+            let result = self.accept_node(&node)?;
             match result {
                 // "2. If result is FILTER_ACCEPT, then set the currentNode
                 //     attribute to node and return node."
@@ -350,7 +350,7 @@ impl TreeWalker {
                 // "1. Set node to sibling."
                 node = sibling_op.unwrap();
                 // "2. Filter node and let result be the return value."
-                let result = try!(self.accept_node(&node));
+                let result = self.accept_node(&node)?;
                 // "3. If result is FILTER_ACCEPT, then set the currentNode
                 //     attribute to node and return node."
                 if NodeFilterConstants::FILTER_ACCEPT == result {
@@ -378,7 +378,7 @@ impl TreeWalker {
                 // "5. Filter node and if the return value is FILTER_ACCEPT, then return null."
                 Some(n) => {
                     node = n;
-                    if NodeFilterConstants::FILTER_ACCEPT == try!(self.accept_node(&node)) {
+                    if NodeFilterConstants::FILTER_ACCEPT == self.accept_node(&node)? {
                         return Ok(None)
                     }
                 }
diff --git a/components/script/dom/vrdisplay.rs b/components/script/dom/vrdisplay.rs
index da5c12e8c54..ef611b6224f 100644
--- a/components/script/dom/vrdisplay.rs
+++ b/components/script/dom/vrdisplay.rs
@@ -636,8 +636,8 @@ fn validate_layer(cx: *mut JSContext,
     let ctx = layer.source.as_ref().map(|ref s| s.get_or_init_webgl_context(cx, None)).unwrap_or(None);
     if let Some(ctx) = ctx {
         let mut data = WebVRLayer::default();
-        try!(parse_bounds(&layer.leftBounds, &mut data.left_bounds));
-        try!(parse_bounds(&layer.rightBounds, &mut data.right_bounds));
+        parse_bounds(&layer.leftBounds, &mut data.left_bounds)?;
+        parse_bounds(&layer.rightBounds, &mut data.right_bounds)?;
         Ok((data, ctx))
     } else {
         Err("VRLayer source must be a WebGL Context")
diff --git a/components/script/dom/webgl_validations/tex_image_2d.rs b/components/script/dom/webgl_validations/tex_image_2d.rs
index f77d80c2715..0694af9512b 100644
--- a/components/script/dom/webgl_validations/tex_image_2d.rs
+++ b/components/script/dom/webgl_validations/tex_image_2d.rs
@@ -285,7 +285,7 @@ impl<'a> WebGLValidator for TexImage2DValidator<'a> {
             width,
             height,
             border,
-        } = try!(self.common_validator.validate());
+        } = self.common_validator.validate()?;
 
         // GL_INVALID_VALUE is generated if target is one of the six cube map 2D
         // image targets and the width and height parameters are not equal.
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index f2043cf3eb2..c8bbba63f53 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1496,7 +1496,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         typedarray!(in(cx) let array_buffer: ArrayBuffer = data);
         let data_vec = match array_buffer {
             Ok(mut data) => data.as_slice().to_vec(),
-            Err(_) => try!(fallible_array_buffer_view_to_vec(cx, data)),
+            Err(_) => fallible_array_buffer_view_to_vec(cx, data)?,
         };
 
         let bound_buffer = match target {
@@ -1564,7 +1564,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         typedarray!(in(cx) let array_buffer: ArrayBuffer = data);
         let data_vec = match array_buffer {
             Ok(mut data) => data.as_slice().to_vec(),
-            Err(_) => try!(fallible_array_buffer_view_to_vec(cx, data)),
+            Err(_) => fallible_array_buffer_view_to_vec(cx, data)?,
         };
 
         let bound_buffer = match target {
@@ -1596,7 +1596,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.8
     unsafe fn CompressedTexImage2D(&self, cx: *mut JSContext, _target: u32, _level: i32, _internal_format: u32,
                             _width: i32, _height: i32, _border: i32, pixels: *mut JSObject) -> Fallible<()> {
-        let _data = try!(fallible_array_buffer_view_to_vec(cx, pixels) );
+        let _data = fallible_array_buffer_view_to_vec(cx, pixels)?;
         // FIXME: No compressed texture format is currently supported, so error out as per
         // https://www.khronos.org/registry/webgl/specs/latest/1.0/#COMPRESSED_TEXTURE_SUPPORT
         self.webgl_error(InvalidEnum);
@@ -1608,7 +1608,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     unsafe fn CompressedTexSubImage2D(&self, cx: *mut JSContext, _target: u32, _level: i32,
                                _xoffset: i32, _yoffset: i32, _width: i32, _height: i32,
                                _format: u32, pixels: *mut JSObject) -> Fallible<()> {
-        let _data = try!(fallible_array_buffer_view_to_vec(cx, pixels));
+        let _data = fallible_array_buffer_view_to_vec(cx, pixels)?;
         // FIXME: No compressed texture format is currently supported, so error out as per
         // https://www.khronos.org/registry/webgl/specs/latest/1.0/#COMPRESSED_TEXTURE_SUPPORT
         self.webgl_error(InvalidEnum);
@@ -2682,7 +2682,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default));
+        let data_vec = typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default)?;
 
         if self.validate_uniform_parameters(uniform, UniformSetterType::Int, &data_vec) {
             self.ipc_renderer
@@ -2700,7 +2700,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
 
         if self.validate_uniform_parameters(uniform, UniformSetterType::Float, &data_vec) {
             self.ipc_renderer
@@ -2729,7 +2729,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatVec2,
@@ -2762,7 +2762,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default));
+        let data_vec = typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default)?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::IntVec2,
@@ -2795,7 +2795,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatVec3,
@@ -2828,7 +2828,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default));
+        let data_vec = typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default)?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::IntVec3,
@@ -2862,7 +2862,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default));
+        let data_vec = typed_array_or_sequence_to_vec::<Int32>(cx, data, ConversionBehavior::Default)?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::IntVec4,
@@ -2895,7 +2895,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                   uniform: Option<&WebGLUniformLocation>,
                   data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
 
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatVec4,
@@ -2916,7 +2916,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                         transpose: bool,
                         data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatMat2,
                                             &data_vec) {
@@ -2936,7 +2936,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                         transpose: bool,
                         data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatMat3,
                                             &data_vec) {
@@ -2956,7 +2956,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
                         transpose: bool,
                         data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if self.validate_uniform_parameters(uniform,
                                             UniformSetterType::FloatMat4,
                                             &data_vec) {
@@ -2996,7 +2996,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     #[allow(unsafe_code)]
     unsafe fn VertexAttrib1fv(&self, cx: *mut JSContext, indx: u32, data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if data_vec.len() < 1 {
             return Ok(self.webgl_error(InvalidOperation));
         }
@@ -3013,7 +3013,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     #[allow(unsafe_code)]
     unsafe fn VertexAttrib2fv(&self, cx: *mut JSContext, indx: u32, data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if data_vec.len() < 2 {
             return Ok(self.webgl_error(InvalidOperation));
         }
@@ -3030,7 +3030,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     #[allow(unsafe_code)]
     unsafe fn VertexAttrib3fv(&self, cx: *mut JSContext, indx: u32, data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if data_vec.len() < 3 {
             return Ok(self.webgl_error(InvalidOperation));
         }
@@ -3047,7 +3047,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     #[allow(unsafe_code)]
     unsafe fn VertexAttrib4fv(&self, cx: *mut JSContext, indx: u32, data: *mut JSObject) -> Fallible<()> {
         assert!(!data.is_null());
-        let data_vec = try!(typed_array_or_sequence_to_vec::<Float32>(cx, data, ()));
+        let data_vec = typed_array_or_sequence_to_vec::<Float32>(cx, data, ())?;
         if data_vec.len() < 4 {
             return Ok(self.webgl_error(InvalidOperation));
         }
@@ -3134,7 +3134,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         let data = if data_ptr.is_null() {
             None
         } else {
-            Some(try!(fallible_array_buffer_view_to_vec(cx, data_ptr)))
+            Some(fallible_array_buffer_view_to_vec(cx, data_ptr)?)
         };
 
         let validator = TexImage2DValidator::new(self, target, level,
@@ -3261,7 +3261,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         let data = if data_ptr.is_null() {
             None
         } else {
-            Some(try!(fallible_array_buffer_view_to_vec(cx, data_ptr)))
+            Some(fallible_array_buffer_view_to_vec(cx, data_ptr)?)
         };
 
         let validator = TexImage2DValidator::new(self, target, level,
diff --git a/components/script/dom/websocket.rs b/components/script/dom/websocket.rs
index ec69eb93346..b533789e611 100644
--- a/components/script/dom/websocket.rs
+++ b/components/script/dom/websocket.rs
@@ -316,7 +316,7 @@ impl WebSocketMethods for WebSocket {
     // https://html.spec.whatwg.org/multipage/#dom-websocket-send
     fn Send(&self, data: USVString) -> ErrorResult {
         let data_byte_len = data.0.as_bytes().len() as u64;
-        let send_data = try!(self.send_impl(data_byte_len));
+        let send_data = self.send_impl(data_byte_len)?;
 
         if send_data {
             let mut other_sender = self.sender.borrow_mut();
@@ -334,7 +334,7 @@ impl WebSocketMethods for WebSocket {
            If the buffer limit is reached in the first place, there are likely other major problems
         */
         let data_byte_len = blob.Size();
-        let send_data = try!(self.send_impl(data_byte_len));
+        let send_data = self.send_impl(data_byte_len)?;
 
         if send_data {
             let mut other_sender = self.sender.borrow_mut();
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 1f6a7c26eea..0d4dca7d845 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -765,7 +765,7 @@ impl WindowMethods for Window {
 
         // Step 1-2, 6-8.
         // TODO(#12717): Should implement the `transfer` argument.
-        let data = try!(StructuredCloneData::write(cx, message));
+        let data = StructuredCloneData::write(cx, message)?;
 
         // Step 9.
         self.post_message(origin, data);
@@ -993,9 +993,9 @@ impl WindowMethods for Window {
 
     // check-tidy: no specs after this line
     fn OpenURLInDefaultBrowser(&self, href: DOMString) -> ErrorResult {
-        let url = try!(ServoUrl::parse(&href).map_err(|e| {
+        let url = ServoUrl::parse(&href).map_err(|e| {
             Error::Type(format!("Couldn't parse URL: {}", e))
-        }));
+        })?;
         match open::that(url.as_str()) {
             Ok(_) => Ok(()),
             Err(e) => Err(Error::Type(format!("Couldn't open URL: {}", e))),
diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 1fb354189e3..68655c89981 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -167,7 +167,7 @@ impl WorkerMethods for Worker {
     #[allow(unsafe_code)]
     // https://html.spec.whatwg.org/multipage/#dom-worker-postmessage
     unsafe fn PostMessage(&self, cx: *mut JSContext, message: HandleValue) -> ErrorResult {
-        let data = try!(StructuredCloneData::write(cx, message));
+        let data = StructuredCloneData::write(cx, message)?;
         let address = Trusted::new(self);
 
         // NOTE: step 9 of https://html.spec.whatwg.org/multipage/#dom-messageport-postmessage
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index bd4af97d347..76cb5810986 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -501,7 +501,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
         // Step 4 (first half)
         let extracted_or_serialized = match data {
             Some(DocumentOrBodyInit::Document(ref doc)) => {
-                let data = Vec::from(try!(serialize_document(&doc)).as_ref());
+                let data = Vec::from(serialize_document(&doc)?.as_ref());
                 let content_type = if doc.is_html_document() {
                     "text/html;charset=UTF-8"
                 } else {
@@ -719,7 +719,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
             _ => {},
         }
         // Step 2
-        let override_mime = try!(mime.parse::<Mime>().map_err(|_| Error::Syntax));
+        let override_mime = mime.parse::<Mime>().map_err(|_| Error::Syntax)?;
         // Step 3
         let mime_no_params = Mime(override_mime.clone().0, override_mime.clone().1, vec![]);
         *self.override_mime_type.borrow_mut() = Some(mime_no_params);
diff --git a/components/script/layout_wrapper.rs b/components/script/layout_wrapper.rs
index 1d28242e926..aaaf5cce107 100644
--- a/components/script/layout_wrapper.rs
+++ b/components/script/layout_wrapper.rs
@@ -371,9 +371,9 @@ pub struct ServoLayoutElement<'le> {
 
 impl<'le> fmt::Debug for ServoLayoutElement<'le> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        try!(write!(f, "<{}", self.element.local_name()));
+        write!(f, "<{}", self.element.local_name())?;
         if let &Some(ref id) = unsafe { &*self.element.id_attribute() } {
-            try!(write!(f, " id={}", id));
+            write!(f, " id={}", id)?;
         }
         write!(f, "> ({:#x})", self.as_node().opaque().0)
     }