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authorNorbert Preining <preining@logic.at>2010-05-12 16:54:37 +0000
committerNorbert Preining <preining@logic.at>2010-05-12 16:54:37 +0000
commit661c41a09e39a182865e0b51e34cc995a0dc96e8 (patch)
tree2f79bb1406e22fdcb2587be8ffda6c0c609d7932 /Master/tlpkg/tlperl/lib/Search
parentb645030efc22e13c2498a1522083634ab91b2de1 (diff)
move tlperl.straw to tlperl
git-svn-id: svn://tug.org/texlive/trunk@18210 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/tlpkg/tlperl/lib/Search')
-rwxr-xr-xMaster/tlpkg/tlperl/lib/Search/Dict.pm108
1 files changed, 108 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl/lib/Search/Dict.pm b/Master/tlpkg/tlperl/lib/Search/Dict.pm
new file mode 100755
index 00000000000..199fa5f9b41
--- /dev/null
+++ b/Master/tlpkg/tlperl/lib/Search/Dict.pm
@@ -0,0 +1,108 @@
+package Search::Dict;
+require 5.000;
+require Exporter;
+
+use strict;
+
+our $VERSION = '1.02';
+our @ISA = qw(Exporter);
+our @EXPORT = qw(look);
+
+=head1 NAME
+
+Search::Dict, look - search for key in dictionary file
+
+=head1 SYNOPSIS
+
+ use Search::Dict;
+ look *FILEHANDLE, $key, $dict, $fold;
+
+ use Search::Dict;
+ look *FILEHANDLE, $params;
+
+=head1 DESCRIPTION
+
+Sets file position in FILEHANDLE to be first line greater than or equal
+(stringwise) to I<$key>. Returns the new file position, or -1 if an error
+occurs.
+
+The flags specify dictionary order and case folding:
+
+If I<$dict> is true, search by dictionary order (ignore anything but word
+characters and whitespace). The default is honour all characters.
+
+If I<$fold> is true, ignore case. The default is to honour case.
+
+If there are only three arguments and the third argument is a hash
+reference, the keys of that hash can have values C<dict>, C<fold>, and
+C<comp> or C<xfrm> (see below), and their correponding values will be
+used as the parameters.
+
+If a comparison subroutine (comp) is defined, it must return less than zero,
+zero, or greater than zero, if the first comparand is less than,
+equal, or greater than the second comparand.
+
+If a transformation subroutine (xfrm) is defined, its value is used to
+transform the lines read from the filehandle before their comparison.
+
+=cut
+
+sub look {
+ my($fh,$key,$dict,$fold) = @_;
+ my ($comp, $xfrm);
+ if (@_ == 3 && ref $dict eq 'HASH') {
+ my $params = $dict;
+ $dict = 0;
+ $dict = $params->{dict} if exists $params->{dict};
+ $fold = $params->{fold} if exists $params->{fold};
+ $comp = $params->{comp} if exists $params->{comp};
+ $xfrm = $params->{xfrm} if exists $params->{xfrm};
+ }
+ $comp = sub { $_[0] cmp $_[1] } unless defined $comp;
+ local($_);
+ my(@stat) = stat($fh)
+ or return -1;
+ my($size, $blksize) = @stat[7,11];
+ $blksize ||= 8192;
+ $key =~ s/[^\w\s]//g if $dict;
+ $key = lc $key if $fold;
+ # find the right block
+ my($min, $max) = (0, int($size / $blksize));
+ my $mid;
+ while ($max - $min > 1) {
+ $mid = int(($max + $min) / 2);
+ seek($fh, $mid * $blksize, 0)
+ or return -1;
+ <$fh> if $mid; # probably a partial line
+ $_ = <$fh>;
+ $_ = $xfrm->($_) if defined $xfrm;
+ chomp;
+ s/[^\w\s]//g if $dict;
+ $_ = lc $_ if $fold;
+ if (defined($_) && $comp->($_, $key) < 0) {
+ $min = $mid;
+ }
+ else {
+ $max = $mid;
+ }
+ }
+ # find the right line
+ $min *= $blksize;
+ seek($fh,$min,0)
+ or return -1;
+ <$fh> if $min;
+ for (;;) {
+ $min = tell($fh);
+ defined($_ = <$fh>)
+ or last;
+ $_ = $xfrm->($_) if defined $xfrm;
+ chomp;
+ s/[^\w\s]//g if $dict;
+ $_ = lc $_ if $fold;
+ last if $comp->($_, $key) >= 0;
+ }
+ seek($fh,$min,0);
+ $min;
+}
+
+1;