Make JSLint clean code

[Constellation]

We should make this JSLint clean code.

[ThomasR]

May I suggest using ESLint instead?

JSLint is really a pain. I've given up trying to refactor everything.

[michaelficarra]

:+1: jslint is and always has been a terrible tool.

[ThomasR]

To be fair, JSLint actually helps in many cases.

Its opinionated stylistic rules* mostly lead to cleaner loops, even though they're sometimes just getting in the way.

The only real issue that I've seen so far is return delete node.loc;, which makes no sense in strict mode — Should be try { delete node.loc; return true; } catch(e) { return false; }

*_{no for, no continue, no while(true)}