X-Git-Url: http://git.shiar.net/perl/list-index.git/blobdiff_plain/a621cd10e5c167968a778cb6a1a4f319d4949a7a..319dd675faee700a9fa0485863889a661ef9dc53:/lib/List/Index.pm?ds=sidebyside
diff --git a/lib/List/Index.pm b/lib/List/Index.pm
index 513ce4f..00f2bdb 100644
--- a/lib/List/Index.pm
+++ b/lib/List/Index.pm
@@ -4,11 +4,14 @@ use 5.010;
use strict;
use warnings;
-our $VERSION = '1.00';
+use Exporter 'import';
+
+our $VERSION = '1.01';
+our @EXPORT_OK = qw(rangematch);
sub new {
my ($class, $values) = @_;
- bless [map { tr/{/./; $_ } sort map { s/[^a-z]/{/g; $_ } @$values], $class;
+ bless [sort map { s/[^a-z]/./g; $_ } @$values], $class;
}
sub ranges {
@@ -26,7 +29,7 @@ sub ranges {
my $link = substr $self->[$offset], 0, $length;
if ($context) {
my $trim = 1;
- my $before = $offset > $context ? $self->[$offset - $context] : '';
+ my $before = $offset > $context ? $self->[$offset - $context] : '.';
for my $match (split //, $before) {
scalar $link =~ /\G\Q$match/g or last;
$trim++;
@@ -40,8 +43,9 @@ sub ranges {
for my $i (0 .. $#links - 1) {
my ($link, $lastchar) = $links[$i + 1]->[0] =~ /(.*)(.)/;
- $link .= $lastchar eq '.' ? 'z' : chr( ord($lastchar) - 1 )
- unless $lastchar eq 'a';
+ $link .= $lastchar eq 'a' ? '.' : chr( ord($lastchar) - 1 )
+ unless $lastchar eq '.';
+ next if $link eq $links[$i]->[0];
$links[$i]->[1] = $link;
}
$links[-1]->[1] = '';
@@ -49,6 +53,67 @@ sub ranges {
return \@links;
}
+sub rangematch {
+ my ($link) = @_;
+ my ($s1, $s2) = $link =~ /([^-]*) - ([^-]*)/x
+ or return qr/^\Q$link/i;
+ my @allow;
+
+ if (length $s1) {
+ if (length $s2) {
+ $s1 le $s2 or $s1 =~ /^\Q$s2/ or return undef;
+ }
+
+ my $prefix = '';
+ my $char;
+ for my $i (0 .. length($s1) - 1) {
+ $char = substr $s1, $i, 1;
+ my $next = $char;
+ $next = chr( ord($char) + 1 ) if length $s1 > $i + 1;
+ my $last = 'z';
+ if (length $s2 > $i) {
+ if ($s2 =~ /^\Q$prefix/) {
+ $last = substr $s2, $i, 1;
+ next if $char eq $last;
+ $last = chr( ord($last) - (length $s2 > 1) );
+ next if $next gt $last;
+ }
+ }
+ push @allow, $prefix."[$next-$last]";
+ }
+ continue {
+ $prefix .= $char;
+ }
+ }
+
+ if (length $s2) {
+ my $prefix = '';
+ my $char;
+ for my $i (0 .. length($s2) - 1) {
+ $char = substr $s2, $i, 1;
+ my $last = 'z';
+ if (length $s1 > $i) {
+ my $c1 = substr $s1, $i, 1;
+ if ($s1 =~ /^\Q$prefix/) {
+ next if $c1 le $char;
+ }
+ }
+ push @allow, $prefix."(?![$char-$last])"
+ if $i or $s1 eq '';
+ }
+ continue {
+ $prefix .= $char;
+ }
+
+ push @allow, $prefix
+ if $s2 =~ /^\Q$prefix/ and $s1 le $s2
+ and not (length $s2 == 1 && length $s1 >= length $s2 && $s1 ne $s2);
+ }
+
+ my $match = sprintf @allow <= 1 ? '%s' : '(?:%s)', join('|', @allow);
+ return qr/^$match/i;
+}
+
1;
__END__
@@ -62,7 +127,11 @@ List::Index - Paginate alphabetic entries by finding minimal prefixes
use List::Index;
my $index = List::Index->new(\@values);
my @pages = $index->ranges({pagesize => 50});
- printf '%1$s ', @$_ for @pages;
+ printf '%1$s ', @$_ for @pages;
+
+ use List::Index 'rangematch';
+ my $limit = rangematch('b-bmq'); # matches prefix like 'baa'..'bmq'
+ @results = grep { $limit } @results;
=head1 DESCRIPTION