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1. Embed this notice
   Rich Felker (dalias@hachyderm.io)'s status on Saturday, 30-Nov-2024 10:52:35 JST Rich Felker

   in reply to

   • mcc
   • luna, only carbon now

   @mcc @luna IMO if reversal of += is a concern, the reverse form without a space should just be a syntax error, not silently do something different.

   • Embed this notice
     mcc (mcc@mastodon.social)'s status on Saturday, 30-Nov-2024 10:52:36 JST mcc

     in reply to

     • luna, only carbon now

     @luna In my opinion, += and =+ should do the same thing, but in opposite order, similar to the difference between a++ and ++a. Nobody ever lets me design a programming language

   • Embed this notice
     luna, only carbon now (luna@pony.social)'s status on Saturday, 30-Nov-2024 10:52:37 JST luna, only carbon now

     [alright, let's try this one again, hopefully I didn’t make any glaring errors this time]

     Did you know that humans are fallible?

     Did you know that programmers are humans?

     Did you know that sometimes programmers make typos?

     Did you know that you can mistype a += b as a =+ b and it’ll still compile/run, so long as the language you’re programming in has a unary plus operator, and the return type of +b is assignable to a?

     Did you know that it’s even easier to make the same mistake with a -= b as a =- b because unary minus seems to be more commonly available?

     Did you know that you can also do this with if (a != b) as if (a =! b) in cases where the result of an assignment expression can be interpreted as a bool, a is mutable, and the unary not operator is also a thing that exists?

     Did you know that you can catch the latter case by making a immutable, but that won’t work for the earlier cases?

     Did you know that these mistakes might be slightly easier to spot if you use a code formatter that rearranges the whitespace to a = +b etc, but even that still depends on the reader noticing the discrepancy between the intended behavior and the code as written, and in the case of a = -b it might even be harder to spot that something’s wrong?

     Did you know that in JavaScript you can typo if (a >= b) as if (a => b) and neither immutability nor the formatter will save you? (But a good linter might.)

     Note: The correct response to everything I’ve just written is “oh no”.

     (also on my blog, with additional footnotes: https://moonbase.lgbt/blog/operator-transposition/)