ES6 modules default exported function/class/generator name is not declared

[falsandtru]

// function
export default function foo() {
}
export {foo}; // hello.ts(3,9): error TS2304: Cannot find name 'foo'.

// generator
export default function *foo() {
}
export {foo}; // hello.ts(3,9): error TS2304: Cannot find name 'foo'.

// class
export default class Foo {
}
export {Foo}; // hello.ts(3,9): error TS2304: Cannot find name 'Foo'.

// hoistable
export {foo}; // hello.ts(1,9): error TS2304: Cannot find name 'foo'.
export default function foo() {
}

http://www.ecma-international.org/ecma-262/6.0/#sec-source-text-module-records
http://www.ecma-international.org/ecma-262/6.0/#table-42

[WangJi]

is this fixed in 1.8?

[sandersn]

Not yet. I haven't had a chance to look at it.

[sandersn]

It looks like an earlier fix (41e3973) prevents exported identifiers from being available to namespaces that have merged with the module in question. It doesn't take into account that default actually does introduce a local name.

[mhegazy]

@WangJi and @falsandtru can you give tonight's typescript@next a try.

[WangJi]

Tried on Version 1.8.0-dev.20151112, still got the same warning.
And

export default class Foo{
}

is complied into

exports.Foo = Foo; //instead of default

[sandersn]

This bug fix indeed only fixes the name resolution, not the emit. Although the emit is wrong for classes but not functions. I'll open a separate bug for the incorrect emit.

[sandersn]

And it only happens when the target is ES6, not ES5.

[sandersn]

Turns out the bug is already known: #5594