package Text::Abbrev; require 5.005; # Probably works on earlier versions too. require Exporter; our $VERSION = '1.01'; =head1 NAME abbrev - create an abbreviation table from a list =head1 SYNOPSIS use Text::Abbrev; abbrev $hashref, LIST =head1 DESCRIPTION Stores all unambiguous truncations of each element of LIST as keys in the associative array referenced by C<$hashref>. The values are the original list elements. =head1 EXAMPLE $hashref = abbrev qw(list edit send abort gripe); %hash = abbrev qw(list edit send abort gripe); abbrev $hashref, qw(list edit send abort gripe); abbrev(*hash, qw(list edit send abort gripe)); =cut @ISA = qw(Exporter); @EXPORT = qw(abbrev); # Usage: # abbrev \%foo, LIST; # ... # $long = $foo{$short}; sub abbrev { my ($word, $hashref, $glob, %table, $returnvoid); @_ or return; # So we don't autovivify onto @_ and trigger warning if (ref($_[0])) { # hash reference preferably $hashref = shift; $returnvoid = 1; } elsif (ref \$_[0] eq 'GLOB') { # is actually a glob (deprecated) $hashref = \%{shift()}; $returnvoid = 1; } %{$hashref} = (); WORD: foreach $word (@_) { for (my $len = (length $word) - 1; $len > 0; --$len) { my $abbrev = substr($word,0,$len); my $seen = ++$table{$abbrev}; if ($seen == 1) { # We're the first word so far to have # this abbreviation. $hashref->{$abbrev} = $word; } elsif ($seen == 2) { # We're the second word to have this # abbreviation, so we can't use it. delete $hashref->{$abbrev}; } else { # We're the third word to have this # abbreviation, so skip to the next word. next WORD; } } } # Non-abbreviations always get entered, even if they aren't unique foreach $word (@_) { $hashref->{$word} = $word; } return if $returnvoid; if (wantarray) { %{$hashref}; } else { $hashref; } } 1;