It's hard to look outside the box, almost by definition. So what follows aren't really suggestions for syntax, they're more questions for "what's a good idiom for?"

The "loop-and-a-half" problem has already been mentioned, but I still haven't seen anything that looks really good (though the redo aproach may be the cleanest).

Something I've frequently found myself doing is wanting a three-way control structure for greater than, less than, and equal to. Sure there are ways to do it, but none of them really feel clean. 

given fork {
  case $_ < 0 {
    #error
  }
  case $_ > 0 {
    #parent
  }
  default {
    #child
  }
}

[download]
or 
if ((my $pid = fork()) < 0){
   #error
} elsif ($pid > 0) {
   #parent
} else {
   $child
}

[download]
But it's the sort of thing that feels like it could be simpler. A better example might be checking two values against each other, where it feels unnatural to need a separate variable or compare them multiple times. 
if (get_the_boundary_x() < the_user_provided_x()){
   draw_color("green");
elsif (get_the_boundary_x() == the_user_provided_x()){
   draw_color("blue");
else {
   draw_color("red");
}

[download]
(Yes, I know that can be done with draw_color(qw( blue red green )[get_the_boundary_x() <=> the_user_provided_x()], but that's just ugly and confusing).

merlyn's looking for a good idiom: return this if this is true shows another question without a (really good, or at least completely natural) answer. The suggested if (my $ret = thatroutine()){return $ret} feels ugly due to the synthetic variable $ret.

In reply to Re: Control Structures by Eimi Metamorphoumai
in thread Control Structures by artist

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