function doSomething(a : any) {
let b = (a as Array<any>)
alert(typeof b) // displays "string"
}
doSomething("Hello")
The alert is showing "string" instead of what I anticipated, which was something along the lines of a null value. The documentation on the as operator seems to be scarce. Perhaps you can refer to this link for more information.
You might also find this related question helpful.
Do I still need to manually check the type of variable b?
Both the as operator and the <T>expr assertion syntax are essentially the same, with the only difference being in their syntax. They do not affect runtime behavior in any way.
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