ES6 modules cannot use "await" as an identifier

[evmar]

According to http://www.ecma-international.org/ecma-262/6.0/#sec-future-reserved-words
"await is only treated as a FutureReservedWord when Module is the goal symbol of the syntactic grammar."

This code should be illegal I think:
http://www.typescriptlang.org/play/#src=import%20'foo'%3B%0A%0Alet%20await%20%3D%203%3B

Came up when discussing TS semantics with @ajklein (v8 ES6 module expert).

[yortus]

Also note the qualification in section 10.2:

Module code is source text that is code that is provided as a ModuleBody. It is the code that is directly evaluated when a module is initialized. The module code of a particular module does not include any source text that is parsed as part of a nested FunctionDeclaration, FunctionExpression, GeneratorDeclaration, GeneratorExpression, MethodDefinition, ArrowFunction, ClassDeclaration, or ClassExpression.

So the OP's playground example is definitely not allowed, but given the above quote I think the following is allowed in an ES6 module:

export function foo() {
    let await = 3;
}

[bterlson]

@yortus, await is a reserved whenever the syntactic goal symbol is Module which is when parsing the entire module script. Thus, await is never allowed as an identifier in a module. The Module goal symbol is a distinct concept from "module code". See 5.1.1.

[yortus]

@bterlson thanks for the clarification. So we are losing another identifier to keywordland 😞 Pity it couldn't be treated as a contextual keyword like async.