There is not a single reason why %hash[key]? is less acceptable than %hash{key} in Perl6

You're perfectly correct. There's not a single reason; there are (at least) five:

  1. We're trying to retain at least some backwards compatibility in the syntax for variable accesses,

  2. Not distinguishing statically between hash and array look-ups severely limits opportunities for fundamental optimizations,

  3. Not distinguishing statically between hash and array look-ups reduces our ability to do compile-time error detection,

  4. Even without error checking, programmers are much less likely to make mistakes if there is three characters' difference between a hash look-up and an array look-up, rather than just a single sigil (that's why we inflect both noun and verb when making plurals in English),

  5. Unless we distinguish hash and array look-ups, there's no way to create objects that can be used as both, according to need (e.g. we can't fix caller to allow named return elements, and we can't allow regexes to simultaneously return their numbered captures as an array and their named captures as a hash.

In reply to Re: (ichi) 2.times('Re: ') Apocalypse 5 and regexes by TheDamian
in thread Apocalypse 5 and regexes by c-era

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