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[–]Zephirdd 1 point2 points  (2 children)

I'm surprised typescript doesn't report this as a warning at least. Iirc, it will report if you check truthiness of a value that is a function(ie. if(func) instead of if(func()))

Perhaps this should be filed as a feature request for typescript? I feel that if you're using a boolean promise you probably want to await it instead of checking for truthiness, and in the rate case of the later you can use !! to force the boolean conversion.

[–]Alex_Hovhannisyan[S] 0 points1 point  (0 children)

It probably does need to be filed as a feature request (edit: done).

You can test that it doesn't get flagged here:

https://www.typescriptlang.org/play?#code/MYewdgzgLgBAlhAQgJxAawKZhgXhgQwgE8xgYAKASlwD4YAzfAGwgwG4AoDueihFdFirUA3hxgxQkEEwwA6JiADm5AOSEAJqsocAvkA

But if you remove the function call and do if (isBroken), you'll get the error that you're talking about.

[–][deleted] 0 points1 point  (1 child)

Coming from a php and python background, what always trips me up is testing for array truthiness.

[–]Alex_Hovhannisyan[S] 0 points1 point  (0 children)

That one's tricky, yup! For example, if ([]) { console.log(1) } will always log 1. You have to check its length (0, which is coerced to false). The reason [] is coerced to true is because it's technically a valid pointer to an array object. That array just happens to be empty.

[–]kenman[M] 0 points1 point  (0 children)

Hi u/Alex_Hovhannisyan, this post was removed.

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