(typeof x == foo) fails to typecheck as (typeof x == 'foo')

[thomaseding]

TypeScript Version: 2.6

Search Terms:
typeof

Code

function test(x: Function | string) { 
    if (typeof x === `function`) { 
        x(); // Typechecker fails to infer callable.
    }
}

Expected behavior:
Program typechecks. (Because changing `function` to 'function' works.)

Actual behavior:
Program does not typecheck.

Playground Link:
https://www.typescriptlang.org/play/#src=function%20test(x%3A%20Function%20%7C%20string)%20%7B%20%0D%0A%20%20%20%20if%20(typeof%20x%20%3D%3D%3D%20%60function%60)%20%7B%20%0D%0A%20%20%20%20%20%20%20%20x()%3B%0D%0A%20%20%20%20%7D%0D%0A%7D

Related Issues:

[ajafff]

Can you try typescript@rc or @next? This should already be fixed.

[RyanCavanaugh]

If you had searched "typeof template", you would have found #20949