Merge pull request #734 from alexcrichton/stabilize

Remove `use_extern_macros` features

.travis.yml

@@ -56,6 +56,7 @@ matrix:
         - cargo test
         # Run the main body of the test suite
         - cargo test --target wasm32-unknown-unknown
+        - cargo test --target wasm32-unknown-unknown --features nightly
         # Rerun the test suite but disable `--debug` in generated JS
         - WASM_BINDGEN_NO_DEBUG=1 cargo test --target wasm32-unknown-unknown
         # Make sure our serde tests work

Cargo.toml

@@ -21,6 +21,7 @@ default = ["spans", "std"]
 spans = ["wasm-bindgen-macro/spans"]
 std = []
 serde-serialize = ["serde", "serde_json", "std"]
+nightly = []
 
 # This is only for debugging wasm-bindgen! No stability guarantees, so enable
 # this at your own peril!

README.md

@@ -13,8 +13,6 @@
 Import JavaScript things into Rust and export Rust things to JavaScript.
 
 ```rust
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 use wasm_bindgen::prelude::*;
 

crates/futures/src/lib.rs

@@ -33,8 +33,6 @@
 //! `Promise`.
 //!
 //! ```rust,no_run
-//! #![feature(use_extern_macros)]
-//!
 //! extern crate futures;
 //! extern crate js_sys;
 //! extern crate wasm_bindgen;
@@ -104,7 +102,6 @@
 //! ```
 
 #![deny(missing_docs)]
-#![feature(use_extern_macros)]
 
 extern crate futures;
 extern crate wasm_bindgen;

crates/futures/tests/tests.rs

@@ -1,4 +1,3 @@
-#![feature(use_extern_macros)]
 #![cfg(target_arch = "wasm32")]
 
 extern crate futures;

crates/js-sys/src/lib.rs

@@ -17,7 +17,6 @@
 //! bindings.
 
 #![doc(html_root_url = "https://docs.rs/js-sys/0.2")]
-#![feature(use_extern_macros)]
 
 extern crate wasm_bindgen;
 

crates/js-sys/tests/headless.rs

@@ -1,4 +1,3 @@
-#![feature(use_extern_macros)]
 #![cfg(target_arch = "wasm32")]
 
 extern crate wasm_bindgen_test;

crates/js-sys/tests/wasm/main.rs

@@ -1,5 +1,4 @@
 #![cfg(target_arch = "wasm32")]
-#![feature(use_extern_macros)]
 #![allow(non_snake_case)]
 
 extern crate js_sys;

crates/macro/ui-tests/attribute-fails-to-parse.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/attribute-fails-to-parse.stderr

@@ -1,7 +1,7 @@
 error: error parsing #[wasm_bindgen] attribute options: failed to parse anything
- --> $DIR/attribute-fails-to-parse.rs:7:16
+ --> $DIR/attribute-fails-to-parse.rs:5:16
   |
-7 | #[wasm_bindgen(nonsense)]
+5 | #[wasm_bindgen(nonsense)]
   |                ^^^^^^^^
 
 error: aborting due to previous error

crates/macro/ui-tests/bad-signatures.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/bad-signatures.stderr

@@ -1,19 +1,19 @@
 error: cannot return a borrowed ref with #[wasm_bindgen]
- --> $DIR/bad-signatures.rs:8:17
+ --> $DIR/bad-signatures.rs:6:17
   |
-8 | pub fn foo() -> &u32 {}
+6 | pub fn foo() -> &u32 {}
   |                 ^^^^
 
 error: unsupported pattern in #[wasm_bindgen] imported function
-  --> $DIR/bad-signatures.rs:12:12
+  --> $DIR/bad-signatures.rs:10:12
    |
-12 |     fn foo(Foo(x): Foo);
+10 |     fn foo(Foo(x): Foo);
    |            ^^^^^^
 
 error: cannot return references in #[wasm_bindgen] imports yet
-  --> $DIR/bad-signatures.rs:14:17
+  --> $DIR/bad-signatures.rs:12:17
    |
-14 |     fn foo() -> &u32;
+12 |     fn foo() -> &u32;
    |                 ^^^^
 
 error: aborting due to 3 previous errors

crates/macro/ui-tests/invalid-attr.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/invalid-attr.stderr

@@ -1,19 +1,19 @@
 error: error parsing #[wasm_bindgen] attribute options: failed to parse anything
- --> $DIR/invalid-attr.rs:7:16
+ --> $DIR/invalid-attr.rs:5:16
   |
-7 | #[wasm_bindgen(x)]
+5 | #[wasm_bindgen(x)]
   |                ^
 
 error: error parsing #[wasm_bindgen] attribute options: failed to parse anything
-  --> $DIR/invalid-attr.rs:12:20
+  --> $DIR/invalid-attr.rs:10:20
    |
-12 |     #[wasm_bindgen(y)]
+10 |     #[wasm_bindgen(y)]
    |                    ^
 
 error: malformed #[wasm_bindgen] attribute
-  --> $DIR/invalid-attr.rs:15:5
+  --> $DIR/invalid-attr.rs:13:5
    |
-15 |     #[wasm_bindgen {  }]
+13 |     #[wasm_bindgen {  }]
    |     ^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 3 previous errors

crates/macro/ui-tests/invalid-enums.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/invalid-enums.stderr

@@ -1,25 +1,25 @@
 error: only public enums are allowed with #[wasm_bindgen]
- --> $DIR/invalid-enums.rs:8:1
+ --> $DIR/invalid-enums.rs:6:1
   |
-8 | enum A {}
+6 | enum A {}
   | ^^^^^^^^^
 
 error: only C-Style enums allowed with #[wasm_bindgen]
-  --> $DIR/invalid-enums.rs:12:6
+  --> $DIR/invalid-enums.rs:10:6
    |
-12 |     D(u32),
+10 |     D(u32),
    |      ^^^^^
 
 error: enums with #[wasm_bidngen] may only have number literal values
-  --> $DIR/invalid-enums.rs:17:9
+  --> $DIR/invalid-enums.rs:15:9
    |
-17 |     X = 1 + 3,
+15 |     X = 1 + 3,
    |         ^^^^^
 
 error: enums with #[wasm_bindgen] can only support numbers that can be represented as u32
-  --> $DIR/invalid-enums.rs:22:9
+  --> $DIR/invalid-enums.rs:20:9
    |
-22 |     X = 4294967296,
+20 |     X = 4294967296,
    |         ^^^^^^^^^^
 
 error: aborting due to 4 previous errors

crates/macro/ui-tests/invalid-imports.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/invalid-imports.stderr

@@ -1,91 +1,91 @@
 error: it is currently not sound to use lifetimes in function signatures
-  --> $DIR/invalid-imports.rs:11:16
-   |
-11 |     fn f() -> &'static u32;
-   |                ^^^^^^^
+ --> $DIR/invalid-imports.rs:9:16
+  |
+9 |     fn f() -> &'static u32;
+  |                ^^^^^^^
 
 error: imported methods must have at least one argument
-  --> $DIR/invalid-imports.rs:14:5
+  --> $DIR/invalid-imports.rs:12:5
    |
-14 |     fn f1();
+12 |     fn f1();
    |     ^^^^^^^^
 
 error: first argument of method must be a shared reference
-  --> $DIR/invalid-imports.rs:16:14
+  --> $DIR/invalid-imports.rs:14:14
    |
-16 |     fn f2(x: u32);
+14 |     fn f2(x: u32);
    |              ^^^
 
 error: first argument of method must be a path
-  --> $DIR/invalid-imports.rs:18:14
+  --> $DIR/invalid-imports.rs:16:14
    |
-18 |     fn f3(x: &&u32);
+16 |     fn f3(x: &&u32);
    |              ^^^^^
 
 error: multi-segment paths are not supported yet
-  --> $DIR/invalid-imports.rs:20:15
+  --> $DIR/invalid-imports.rs:18:15
    |
-20 |     fn f4(x: &foo::Bar);
+18 |     fn f4(x: &foo::Bar);
    |               ^^^^^^^^
 
 error: global paths are not supported yet
+  --> $DIR/invalid-imports.rs:20:15
+   |
+20 |     fn f4(x: &::Bar);
+   |               ^^^^^
+
+error: paths with type parameters are not supported yet
   --> $DIR/invalid-imports.rs:22:15
    |
-22 |     fn f4(x: &::Bar);
-   |               ^^^^^
+22 |     fn f4(x: &Bar<T>);
+   |               ^^^^^^
 
 error: paths with type parameters are not supported yet
   --> $DIR/invalid-imports.rs:24:15
    |
-24 |     fn f4(x: &Bar<T>);
-   |               ^^^^^^
-
-error: paths with type parameters are not supported yet
-  --> $DIR/invalid-imports.rs:26:15
-   |
-26 |     fn f4(x: &Fn(T));
+24 |     fn f4(x: &Fn(T));
    |               ^^^^^
 
 error: constructor returns must be bare types
-  --> $DIR/invalid-imports.rs:29:5
+  --> $DIR/invalid-imports.rs:27:5
    |
-29 |     fn f();
+27 |     fn f();
    |     ^^^^^^^
 
 error: global paths are not supported yet
-  --> $DIR/invalid-imports.rs:31:15
+  --> $DIR/invalid-imports.rs:29:15
    |
-31 |     fn f() -> ::Bar;
+29 |     fn f() -> ::Bar;
    |               ^^^^^
 
 error: return value of constructor must be a bare path
-  --> $DIR/invalid-imports.rs:33:5
+  --> $DIR/invalid-imports.rs:31:5
    |
-33 |     fn f() -> &Bar;
+31 |     fn f() -> &Bar;
    |     ^^^^^^^^^^^^^^^
 
+error: must be Result<...>
+  --> $DIR/invalid-imports.rs:34:15
+   |
+34 |     fn f() -> u32;
+   |               ^^^
+
 error: must be Result<...>
   --> $DIR/invalid-imports.rs:36:15
    |
-36 |     fn f() -> u32;
-   |               ^^^
-
-error: must be Result<...>
-  --> $DIR/invalid-imports.rs:38:15
-   |
-38 |     fn f() -> &u32;
+36 |     fn f() -> &u32;
    |               ^^^^
 
 error: must have at least one generic parameter
-  --> $DIR/invalid-imports.rs:40:15
+  --> $DIR/invalid-imports.rs:38:15
    |
-40 |     fn f() -> Result<>;
+38 |     fn f() -> Result<>;
    |               ^^^^^^^^
 
 error: it is currently not sound to use lifetimes in function signatures
-  --> $DIR/invalid-imports.rs:42:22
+  --> $DIR/invalid-imports.rs:40:22
    |
-42 |     fn f() -> Result<'a>;
+40 |     fn f() -> Result<'a>;
    |                      ^^
 
 error: aborting due to 15 previous errors

crates/macro/ui-tests/invalid-items.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/invalid-items.stderr

@@ -1,67 +1,67 @@
 error: can only #[wasm_bindgen] public functions
- --> $DIR/invalid-items.rs:8:1
+ --> $DIR/invalid-items.rs:6:1
   |
-8 | fn foo() {}
+6 | fn foo() {}
   | ^^^^^^^^^^^
 
 error: can only #[wasm_bindgen] safe functions
-  --> $DIR/invalid-items.rs:11:5
-   |
-11 | pub unsafe fn foo1() {}
-   |     ^^^^^^
+ --> $DIR/invalid-items.rs:9:5
+  |
+9 | pub unsafe fn foo1() {}
+  |     ^^^^^^
 
 error: can only #[wasm_bindgen] non-const functions
-  --> $DIR/invalid-items.rs:14:5
+  --> $DIR/invalid-items.rs:12:5
    |
-14 | pub const fn foo2() {}
+12 | pub const fn foo2() {}
    |     ^^^^^
 
 error: structs with #[wasm_bindgen] cannot have lifetime or type parameters currently
-  --> $DIR/invalid-items.rs:17:11
+  --> $DIR/invalid-items.rs:15:11
    |
-17 | struct Foo<T>(T);
+15 | struct Foo<T>(T);
    |           ^^^
 
 error: cannot import mutable globals yet
-  --> $DIR/invalid-items.rs:21:12
+  --> $DIR/invalid-items.rs:19:12
    |
-21 |     static mut FOO: u32;
+19 |     static mut FOO: u32;
    |            ^^^
 
 error: can't #[wasm_bindgen] variadic functions
-  --> $DIR/invalid-items.rs:23:25
+  --> $DIR/invalid-items.rs:21:25
    |
-23 |     pub fn foo3(x: i32, ...);
+21 |     pub fn foo3(x: i32, ...);
    |                         ^^^
 
 error: only foreign mods with the `C` ABI are allowed
-  --> $DIR/invalid-items.rs:27:8
+  --> $DIR/invalid-items.rs:25:8
    |
-27 | extern "system" {
+25 | extern "system" {
    |        ^^^^^^^^
 
+error: can't #[wasm_bindgen] functions with lifetime or type parameters
+  --> $DIR/invalid-items.rs:29:12
+   |
+29 | pub fn foo4<T>() {}
+   |            ^^^
+
 error: can't #[wasm_bindgen] functions with lifetime or type parameters
   --> $DIR/invalid-items.rs:31:12
    |
-31 | pub fn foo4<T>() {}
-   |            ^^^
+31 | pub fn foo5<'a>() {}
+   |            ^^^^
 
 error: can't #[wasm_bindgen] functions with lifetime or type parameters
   --> $DIR/invalid-items.rs:33:12
    |
-33 | pub fn foo5<'a>() {}
-   |            ^^^^
-
-error: can't #[wasm_bindgen] functions with lifetime or type parameters
-  --> $DIR/invalid-items.rs:35:12
-   |
-35 | pub fn foo6<'a, T>() {}
+33 | pub fn foo6<'a, T>() {}
    |            ^^^^^^^
 
 error: #[wasm_bindgen] can only be applied to a function, struct, enum, impl, or extern block
-  --> $DIR/invalid-items.rs:38:1
+  --> $DIR/invalid-items.rs:36:1
    |
-38 | trait X {}
+36 | trait X {}
    | ^^^^^^^^^^
 
 error: aborting due to 11 previous errors

crates/macro/ui-tests/invalid-methods.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/invalid-methods.stderr

@@ -1,61 +1,61 @@
 error: #[wasm_bindgen] default impls are not supported
-  --> $DIR/invalid-methods.rs:11:1
-   |
-11 | default impl A {
-   | ^^^^^^^
+ --> $DIR/invalid-methods.rs:9:1
+  |
+9 | default impl A {
+  | ^^^^^^^
 
 error: #[wasm_bindgen] unsafe impls are not supported
-  --> $DIR/invalid-methods.rs:15:1
+  --> $DIR/invalid-methods.rs:13:1
    |
-15 | unsafe impl A {
+13 | unsafe impl A {
    | ^^^^^^
 
 error: #[wasm_bindgen] trait impls are not supported
-  --> $DIR/invalid-methods.rs:19:6
+  --> $DIR/invalid-methods.rs:17:6
    |
-19 | impl Clone for A {
+17 | impl Clone for A {
    |      ^^^^^
 
 error: #[wasm_bindgen] generic impls aren't supported
-  --> $DIR/invalid-methods.rs:23:5
+  --> $DIR/invalid-methods.rs:21:5
    |
-23 | impl<T> A {
+21 | impl<T> A {
    |     ^^^
 
 error: unsupported self type in #[wasm_bindgen] impl
-  --> $DIR/invalid-methods.rs:27:6
+  --> $DIR/invalid-methods.rs:25:6
    |
-27 | impl &'static A {
+25 | impl &'static A {
    |      ^^^^^^^^^^
 
 error: const definitions aren't supported with #[wasm_bindgen]
-  --> $DIR/invalid-methods.rs:34:5
+  --> $DIR/invalid-methods.rs:32:5
    |
-34 |     const X: u32 = 3;
+32 |     const X: u32 = 3;
    |     ^^^^^^^^^^^^^^^^^
 
 error: type definitions in impls aren't supported with #[wasm_bindgen]
-  --> $DIR/invalid-methods.rs:35:5
+  --> $DIR/invalid-methods.rs:33:5
    |
-35 |     type Y = u32;
+33 |     type Y = u32;
    |     ^^^^^^^^^^^^^
 
 error: macros in impls aren't supported
-  --> $DIR/invalid-methods.rs:36:5
+  --> $DIR/invalid-methods.rs:34:5
    |
-36 |     x!();
+34 |     x!();
    |     ^^^^^
 
 error: can only #[wasm_bindgen] non-const functions
-  --> $DIR/invalid-methods.rs:41:9
+  --> $DIR/invalid-methods.rs:39:9
    |
-41 |     pub const fn foo() {}
+39 |     pub const fn foo() {}
    |         ^^^^^
 
 error: can only bindgen safe functions
-  --> $DIR/invalid-methods.rs:42:9
+  --> $DIR/invalid-methods.rs:40:9
    |
-42 |     pub unsafe fn foo() {}
+40 |     pub unsafe fn foo() {}
    |         ^^^^^^
 
 error: aborting due to 10 previous errors

crates/macro/ui-tests/non-public-function.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

crates/macro/ui-tests/non-public-function.stderr

@@ -1,7 +1,7 @@
 error: can only #[wasm_bindgen] public functions
- --> $DIR/non-public-function.rs:8:1
+ --> $DIR/non-public-function.rs:6:1
   |
-8 | fn foo() {}
+6 | fn foo() {}
   | ^^^^^^^^^^^
 
 error: aborting due to previous error

crates/test/README.md

@@ -38,8 +38,6 @@ ton of documentation just yet, but a taste of how it works is:
 
   ```rust
   // in tests/wasm.rs
-  #![feature(use_extern_macros)]
-
   extern crate wasm_bindgen_test;
 
   use wasm_bindgen_test::*;

crates/test/sample/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 #[macro_use]
 extern crate futures;
 extern crate js_sys;

crates/test/sample/tests/browser.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate futures;
 extern crate sample;
 extern crate wasm_bindgen;

crates/test/sample/tests/node.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate futures;
 extern crate sample;
 extern crate wasm_bindgen;

crates/test/src/lib.rs

@@ -2,7 +2,6 @@
 //!
 //! More documentation can be found in the README for this crate!
 
-#![feature(use_extern_macros)]
 #![deny(missing_docs)]
 
 extern crate console_error_panic_hook;

crates/web-sys/tests/wasm/main.rs

@@ -1,4 +1,3 @@
-#![feature(use_extern_macros)]
 #![cfg(target_arch = "wasm32")]
 
 extern crate futures;

crates/webidl-tests/main.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate js_sys;
 extern crate wasm_bindgen;
 extern crate wasm_bindgen_test;

examples/add/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/asm.js/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/canvas/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate js_sys;
 extern crate wasm_bindgen;
 extern crate web_sys;

examples/char/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/closures/Cargo.toml

@@ -7,5 +7,5 @@ authors = ["Alex Crichton <alex@alexcrichton.com>"]
 crate-type = ["cdylib"]
 
 [dependencies]
-wasm-bindgen = { path = "../.." }
+wasm-bindgen = { path = "../..", features = ['nightly'] }
 js-sys = { path = "../../crates/js-sys" }

examples/closures/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 extern crate js_sys;
 

examples/comments/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/console_log/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 extern crate web_sys;
 

examples/dom/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/guide-supported-types-examples/src/lib.rs

@@ -1,4 +1,3 @@
-#![feature(use_extern_macros)]
 #![allow(unused_variables, dead_code)]
 
 extern crate wasm_bindgen;

examples/hello_world/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/import_js/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/julia_set/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 use wasm_bindgen::prelude::*;
 

examples/math/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/no_modules/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/performance/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate humantime;
 extern crate wasm_bindgen;
 

examples/smorgasboard/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/wasm-in-wasm/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/webaudio/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros, nll)]
-
 extern crate wasm_bindgen;
 extern crate web_sys;
 
@@ -45,13 +43,20 @@ impl FmOsc {
         // TODO, how to throw from a constructor?
 
         let ctx = web_sys::AudioContext::new().unwrap();
-        let base: &BaseAudioContext = ctx.as_ref();
+        let primary;
+        let fm_osc;
+        let gain;
+        let fm_gain;
 
-        // create our web audio objects
-        let primary = base.create_oscillator().unwrap();
-        let fm_osc = base.create_oscillator().unwrap();
-        let gain = base.create_gain().unwrap();
-        let fm_gain = base.create_gain().unwrap();
+        {
+            let base: &BaseAudioContext = ctx.as_ref();
+
+            // create our web audio objects
+            primary = base.create_oscillator().unwrap();
+            fm_osc = base.create_oscillator().unwrap();
+            gain = base.create_gain().unwrap();
+            fm_gain = base.create_gain().unwrap();
+        }
 
         // some initial settings:
         primary.set_type(OscillatorType::Sine);
@@ -63,27 +68,30 @@ impl FmOsc {
 
 
         // Create base class references:
-        let primary_node: &AudioNode = primary.as_ref();
-        let gain_node: &AudioNode = gain.as_ref();
-        let fm_osc_node: &AudioNode = fm_osc.as_ref();
-        let fm_gain_node: &AudioNode = fm_gain.as_ref();
-        let destination = base.destination();
-        let destination_node: &AudioNode = destination.as_ref();
+        {
+            let primary_node: &AudioNode = primary.as_ref();
+            let gain_node: &AudioNode = gain.as_ref();
+            let fm_osc_node: &AudioNode = fm_osc.as_ref();
+            let fm_gain_node: &AudioNode = fm_gain.as_ref();
+            let base: &BaseAudioContext = ctx.as_ref();
+            let destination = base.destination();
+            let destination_node: &AudioNode = destination.as_ref();
 
 
-        // connect them up:
+            // connect them up:
 
-        // The primary oscillator is routed through the gain node, so that it can control the overall output volume
-        primary_node.connect_with_destination_and_output_and_input_using_destination(gain.as_ref());
-        // Then connect the gain node to the AudioContext destination (aka your speakers)
-        gain_node.connect_with_destination_and_output_and_input_using_destination(destination_node);
+            // The primary oscillator is routed through the gain node, so that it can control the overall output volume
+            primary_node.connect_with_destination_and_output_and_input_using_destination(gain.as_ref());
+            // Then connect the gain node to the AudioContext destination (aka your speakers)
+            gain_node.connect_with_destination_and_output_and_input_using_destination(destination_node);
 
-        // the FM oscillator is connected to its own gain node, so it can control the amount of modulation
-        fm_osc_node.connect_with_destination_and_output_and_input_using_destination(fm_gain.as_ref());
+            // the FM oscillator is connected to its own gain node, so it can control the amount of modulation
+            fm_osc_node.connect_with_destination_and_output_and_input_using_destination(fm_gain.as_ref());
 
-        // Connect the FM oscillator to the frequency parameter of the main oscillator, so that the
-        // FM node can modulate its frequency
-        fm_gain_node.connect_with_destination_and_output_using_destination(&primary.frequency());
+            // Connect the FM oscillator to the frequency parameter of the main oscillator, so that the
+            // FM node can modulate its frequency
+            fm_gain_node.connect_with_destination_and_output_using_destination(&primary.frequency());
+        }
 
 
         // start the oscillators!
@@ -144,4 +152,4 @@ impl FmOsc {
     }
 
 
-}
+}

guide/src/whirlwind-tour/basic-usage.md

@@ -39,8 +39,6 @@ wasm-bindgen = "0.2"
 Next up our actual code! We'll write this in `src/lib.rs`:
 
 ```rust,ignore
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 use wasm_bindgen::prelude::*;
 

guide/src/whirlwind-tour/what-else-can-we-do.md

@@ -5,8 +5,6 @@ can also [explore this code online](https://webassembly.studio/?f=t61j18noqz):
 
 ```rust,ignore
 // src/lib.rs
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

src/closure.rs

@@ -7,6 +7,7 @@
 #![allow(const_err)] // FIXME(rust-lang/rust#52603)
 
 use std::cell::UnsafeCell;
+#[cfg(feature = "nightly")]
 use std::marker::Unsize;
 use std::mem::{self, ManuallyDrop};
 use std::prelude::v1::*;
@@ -90,6 +91,7 @@ impl<T> Closure<T>
     ///
     /// This is unfortunately pretty restrictive for now but hopefully some of
     /// these restrictions can be lifted in the future!
+    #[cfg(feature = "nightly")]
     pub fn new<F>(t: F) -> Closure<T>
         where F: Unsize<T> + 'static
     {

src/lib.rs

@@ -5,9 +5,9 @@
 //! this crate and this crate also provides JS bindings through the `JsValue`
 //! interface.
 
-#![feature(use_extern_macros, unsize)]
 #![no_std]
 #![doc(html_root_url = "https://docs.rs/wasm-bindgen/0.2")]
+#![cfg_attr(feature = "nightly", feature(unsize))]
 
 #[cfg(feature = "serde-serialize")]
 extern crate serde;

tests/crates/a/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

tests/crates/b/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

tests/headless.rs

@@ -1,5 +1,4 @@
 #![cfg(target_arch = "wasm32")]
-#![feature(use_extern_macros)]
 
 extern crate wasm_bindgen_test;
 extern crate wasm_bindgen;

tests/no-std/test.rs

@@ -4,7 +4,6 @@
 //! This doesn't actually run any tests, it's mostly a compile-time verification
 //! that things work.
 
-#![feature(use_extern_macros)]
 #![no_std]
 #![allow(dead_code)]
 

tests/non_wasm.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

tests/std-crate-no-std-dep.rs

@@ -2,7 +2,6 @@
 //! `wasm-bindgen` is compiled itself with the `std` feature and everything
 //! works out just fine.
 
-#![feature(use_extern_macros)]
 #![no_std]
 
 extern crate wasm_bindgen;

tests/wasm/closures.rs

@@ -1,3 +1,5 @@
+#![cfg(feature = "nightly")]
+
 use wasm_bindgen_test::*;
 use wasm_bindgen::prelude::*;
 use std::cell::Cell;

tests/wasm/main.rs

@@ -1,5 +1,4 @@
 #![cfg(target_arch = "wasm32")]
-#![feature(use_extern_macros)]
 
 extern crate wasm_bindgen_test;
 extern crate wasm_bindgen;