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A comment on Microfeatures I'd like to see in more languages. Parent comment

Re:Microfeatures I'd like to see in more languages by david2ndaccount on Thursday January 05, 2023 @11:05PM (#34270833)
`$` refers to the length of the array, so `d[$]` is an array-bounds error. `d[$-1]` is needed for the last element, but you can’t do that blindly, you have to check that the length is nonzero or you’ll get unsigned underflow to ulong.max
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Re:Microfeatures I'd like to see in more languages by WalterBright on Thursday January 05, 2023 @11:47PM (#34271083)
Which will also cause an array-bounds error. So you're covered!
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Re:Microfeatures I'd like to see in more languages by melagonster on Friday January 06, 2023 @03:02AM (#34272170)
perl have $d[$#d] represent the index of last element.
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Re:Microfeatures I'd like to see in more languages by bvrmn on Friday January 06, 2023 @06:27AM (#34273551)
$my_properly_named_array[$#my_properly_named_array] doesn't look like QoL.
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Re:Microfeatures I'd like to see in more languages by tmtvl on Friday January 06, 2023 @07:04AM (#34273785)
Yeah, but $#list is better used for writing loops:

  foreach my $i (0..$#list) {
    say "$i: $list[$i]";
  }
For getting the last element from a list you can just use -1 (and of course further negative numbers work like you would expect, -2 is second to last and so on):

  my @last_three = @items[-1, -2, -3];
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Re:Microfeatures I'd like to see in more languages by melagonster on Friday January 06, 2023 @08:36AM (#34274396)
yes, I forgot perl have negative index!
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