Re:Is there any code in Firefox (as of 2020) that comes from...
by DonHopkins on Saturday March 28, 2020 @02:05AM
(#22709540)
What's hard to document is why there is any need for non-arrow functions.
In the original language design I mean, since non-arrow functions with dynamic "this" only make sense in the context of having been mistakenly baked into the language from day one (or so). If JavaScript started out with only fat arrow functions, and had a simpler way of passing the current object like Python's or CLOS's or Dylan's or ScriptX's explicit "self" parameter, there would have been no confusion or automatic nuclear foot guns or need for two subtly semantically and syntactically different kinds of functions.
Any JavaScript programmer who doesn't clearly understand the difference between non-arrow and arrow functions, and the nuances of dynamically bound "this", and when to use each type of function, is dangerous and libel to write subtly buggy code. Because there should only be one type of function!
There was no reason to design the language and function syntax and semantics in such a mistakenly complex fragile way, that eventually spawned millions of blog posts explaining the nuances and dangers of "this". Because you know that behind every one of those helpful blog posts is a well intentioned programmer who got screwed by "this", and wanted to help other people avoid their mistakes.
I've been programming JavaScript for years, and I STILL get screwed by "this". Whenever something goes inexplicable wrong and I find myself pounding my head up against a cinderblock in frustration because I can't figure it out, I take a step back and search my recent changes for "this", and in most cases, I've just accidentally used a function instead of a fat arrow.
There were plenty of other languages that could have served as examples of the right way to do it, like Smalltalk or Python or Common Lisp CLOS or Dylan, but they were ignored when JavaScript was designed.
In the original language design I mean, since non-arrow functions with dynamic "this" only make sense in the context of having been mistakenly baked into the language from day one (or so). If JavaScript started out with only fat arrow functions, and had a simpler way of passing the current object like Python's or CLOS's or Dylan's or ScriptX's explicit "self" parameter, there would have been no confusion or automatic nuclear foot guns or need for two subtly semantically and syntactically different kinds of functions.
Any JavaScript programmer who doesn't clearly understand the difference between non-arrow and arrow functions, and the nuances of dynamically bound "this", and when to use each type of function, is dangerous and libel to write subtly buggy code. Because there should only be one type of function!
There was no reason to design the language and function syntax and semantics in such a mistakenly complex fragile way, that eventually spawned millions of blog posts explaining the nuances and dangers of "this". Because you know that behind every one of those helpful blog posts is a well intentioned programmer who got screwed by "this", and wanted to help other people avoid their mistakes.
I've been programming JavaScript for years, and I STILL get screwed by "this". Whenever something goes inexplicable wrong and I find myself pounding my head up against a cinderblock in frustration because I can't figure it out, I take a step back and search my recent changes for "this", and in most cases, I've just accidentally used a function instead of a fat arrow.
There were plenty of other languages that could have served as examples of the right way to do it, like Smalltalk or Python or Common Lisp CLOS or Dylan, but they were ignored when JavaScript was designed.