Having the following code:
var abc: [string, number] = [5, "test"];
[ts] Type '[number, string]' is not assignable to type '[string,
Type 'number' is not assignable to type 'string'.
var abc = [5, "test"];
Try out some other types of errors, like mistyped variable names:
var abc: number = 5; console.log(abd);
and you'll see the same thing happen.
Edit: oh, and there is a compiler flag to change this behavior. Using:
tsc --noEmitOnError test.ts
will suppress generating the test.js file if errors are encountered.