The {}s work like parenthesies. I've often wondered why {}s are used in this context, not ()s.

Curlies are used, and not parentheses, because you are actually using code blocks here. It just so happens that usually the block in question is just the contents of a scalar (which happens to be a reference to something)).

There is nothing stopping you from putting more advanced code into that block, such as:

  for my $key( keys %{$moon->phase > 0.25 ? $thisref : $thatref} ) {
    ...
  }

  # or, more likely to be encountered

  push @{$val % 2 ? \@odds : \@evens}, $val;

[download]

But those who come after may not always appreciate your doing so. If you really feel the urge to get fancy, consider calling a subroutine in the code block, if only to let the person drop a breakpoint on the sub so that they can follow exactly what reference is being used.

g r i n d e r
print@_{sort keys %_},$/if%_=split//,'= & *a?b:e\f/h^h!j+n,o@o;r$s-t%t#u';

In reply to Re:x2 Dereferencing hashrefs (why {} and not ()) by grinder
in thread Dereferencing hashrefs by schnarff

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