Add a --no-modules-global flag

This can be used to configure the name of the global that's initialized so it's
not unconditionally `wasm_bindgen`.

Closes #145

README.md

@@ -544,7 +544,8 @@ some notable options are:
   tailored for a web browser. In this mode `window.wasm_bindgen` will be a
   function that takes a path to the wasm file to fetch and instantiate.
   Afterwards exported functions from the wasm are available through
-  `window.wasm_bindgen.foo`.
+  `window.wasm_bindgen.foo`. Note that the name `wasm_bindgen` can be configured
+  with the `--no-modules-global FOO` flag.
 
 * `--typescript` - when passed a `*.d.ts` file will be generated for the
   generated JS file. This should allow hooking into TypeScript projects to

crates/cli-support/src/js/mod.rs

@@ -295,11 +295,15 @@ impl<'a> Context<'a> {
                                 return;
                             }});
                     }};
-                    self.wasm_bindgen = Object.assign(init, __exports);
+                    self.{global_name} = Object.assign(init, __exports);
                 }})();
             ",
                     globals = self.globals,
                     module = module_name,
+                    global_name = self.config.no_modules_global
+                        .as_ref()
+                        .map(|s| &**s)
+                        .unwrap_or("wasm_bindgen"),
             )
         } else {
             let import_wasm = if self.config.nodejs {

crates/cli-support/src/lib.rs

@@ -21,6 +21,7 @@ pub struct Bindgen {
     nodejs: bool,
     browser: bool,
     no_modules: bool,
+    no_modules_global: Option<String>,
     debug: bool,
     typescript: bool,
     demangle: bool,
@@ -42,6 +43,7 @@ impl Bindgen {
             nodejs: false,
             browser: false,
             no_modules: false,
+            no_modules_global: None,
             debug: false,
             typescript: false,
             demangle: true,
@@ -68,6 +70,11 @@ impl Bindgen {
         self
     }
 
+    pub fn no_modules_global(&mut self, name: &str) -> &mut Bindgen {
+        self.no_modules_global = Some(name.to_string());
+        self
+    }
+
     pub fn debug(&mut self, debug: bool) -> &mut Bindgen {
         self.debug = debug;
         self

crates/cli/src/bin/wasm-bindgen.rs

@@ -23,6 +23,7 @@ Options:
     --nodejs                 Generate output that only works in node.js
     --browser                Generate output that only works in a browser
     --no-modules             Generate output that only works in a browser (without modules)
+    --no-modules-global VAR  Name of the global variable to initialize
     --typescript             Output a TypeScript definition file
     --debug                  Include otherwise-extraneous debug checks in output
     --no-demangle            Don't demangle Rust symbol names
@@ -39,6 +40,7 @@ struct Args {
     flag_debug: bool,
     flag_version: bool,
     flag_no_demangle: bool,
+    flag_no_modules_global: Option<String>,
     arg_input: Option<PathBuf>,
 }
 
@@ -65,6 +67,9 @@ fn main() {
         .debug(args.flag_debug)
         .demangle(!args.flag_no_demangle)
         .typescript(args.flag_typescript);
+    if let Some(name) = &args.flag_no_modules_global {
+        b.no_modules_global(name);
+    }
 
     let out_dir = match args.flag_out_dir {
         Some(ref p) => p,