Compiler option for stricter implicit truthy and falsy checks

[ziriax]

We have a large Typescript application, and sometimes we have code like

if (shouldFireNuclearMissiles)...

while we should have written

if (shouldFireNuclearMissiles())...

(pun intended).

So forgetting to evaluate a function results in a truthy value.

I forked the tsc compiler to add basic checks for this in the conditional operator, the if-then-else, while, do and for statements, and that was very easy. We found several bugs in our large code using this forked compiler.

Would such a stricter compiler option (maybe even emitting warnings) be a sound idea?

These automatic truthy and falsy conversions are very handy, but IMHO, for large projects, the comfort they bring does not outweigh the dangers.

Most likely this idea is too much non-Javascript-like, but we're coming from sharp & strongly-typed languages, so I must make this suggestion ;-)

Thanks,
Peter

PS: I first suggested this as a TSLINT rule , but from the friendly feedback I got, it seems this belongs in the compiler instead.

[myitcv]

Covered here palantir/tslint#253 in the actual tslint repository

[RyanCavanaugh]

Duplicate of #7306