Early return instead of "else" causes compiler error.

[radarsu]

TypeScript Version:

nightly (1.9.0-dev.20160217)

Code

let greeting:string;
let x = (message: string | number) => {
        if (typeof message !== "string") {
            return;
        }
        // It's obvious, that message must be a string now. It works with "else statement" but not with early return.
        greeting = message;
    }
}

Expected behavior:
No raising error.

Actual behavior:
Compiler raises an error that type string | number cannot be assigned to string variable.

[mhegazy]

This is working correctly in latest after #8010

[malibuzios]

I tried this in 1.9.0-dev.20160429 (the latest nightly) and it does perform the analysis.

I believe version 1.9.0-dev.20160217 (a nightly build from 17th of February 2016) may not yet include control flow based type analysis, that was only merged on the 23 of April.