Actually, I like passing the arguments so that I can do things like this: (sum doesn't know to look at $a and $b)

use List::Util qw/sum/;
say for map_pairs \&sum, 1..10;
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I do like the aliasing bonus, but it seems to not work on hash keys:

use YAML;
my @array = ( foo_name => " Bob Smiley ", foo_age => " 32" );
map_pairs { $a =~ s/foo_//; s/^\s+//, s/\s+$// for $b; } @array;

print Dump \@array;

my %hash = ( foo_name => " Bob Smiley ", foo_age => " 32" );
map_pairs { $a =~ s/foo_//; s/^\s+//, s/\s+$// for $b; } %hash;

print Dump \%hash;
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outputs

---
- name
- Bob Smiley
- age
- 32
---
foo_age: 32
foo_name: Bob Smiley
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