termcol: 88-colour tables (rgb cube, greyscale ramp)

[sheet.git] / rfc1345convert

diff --git a/rfc1345convert b/rfc1345convert
old mode 100644 (file)
new mode 100755 (executable)
index cf2d937..4fd3940
--- a/rfc1345convert
+++ b/rfc1345convert
@@ -2,26 +2,39 @@
 
 use strict;
 use warnings;
+use utf8;
 
+use open OUT => ':utf8', ':std';
 use Data::Dumper;
 
-our $VERSION = '1.00';
+our $VERSION = '1.01';
 
-if (0) {
-       #TODO: automatic download if not specified on stdin
+# determine input data source
+my $input;
+if (@ARGV) {
+       # manual contents specified (either piped or filename(s) given)
+       $input = \*ARGV;
+}
+else {
+       # automatic download from official website
        require LWP::Simple;
-       LWP::Simple::get('http://www.ietf.org/rfc/rfc1345.txt');
+       my $contents = LWP::Simple::get('http://www.ietf.org/rfc/rfc1345.txt')
+               or die "Couldn't download RFC-1345 from ietf.org";
+       open $input, '<', \$contents;  # emulate file handle
 }
 
 # skip everything until a character indented by 1 space (table start)
-do {$_ = <>} until /^\s\S/;
+do {
+       $_ = readline $input;
+       defined or die "Premature input end";
+} until /^\s\S/;
 
 my @t = $_;  # add first line (already read, assume it's ok)
 
 # read the rest of the character table
-while ($_ = <>) {
+while ($_ = readline $input) {
        # check for table end (chapter 4)
-       last if /^4/;
+       last if /^\d/;
 
        # parse table lines (ignore (unindented) page break)
        next unless s/^ //;
@@ -97,7 +110,7 @@ my @extra;
 if (-r 'shiar.inc.txt') {
        open my $include, '<:utf8', 'shiar.inc.txt';
        for (readline $include) {
-               m{^([!"%'-Z_a-z]{2}) (.)} or next;
+               m{^(\$?[!"%'-Z_a-z]{2}) (.)} or next;
                warn("$1 already defined"), next if defined $di{$1};
                $di{$1} = ord $2;
                push @extra, $1;
@@ -105,6 +118,9 @@ if (-r 'shiar.inc.txt') {
 }
 warn $@ if $@;
 
+$di{chr $_} = $_ for 32 .. 126;
+$di{'\\'.$_} = delete $di{$_} for '{', '}', '\\';
+
 # optionally get unicode character information
 my %info = eval {
        require Unicode::UCD;
@@ -134,6 +150,17 @@ for (keys %di) {
        # show descriptive symbols instead of control chars themselves
        $info{$_}->{string} = $di{$_} < 32 ? chr($di{$_} + 0x2400) : chr(0xFFFD);
 }
+# presentational string for some control(lish) entries
+$info{$_}->{string} = '-' for grep { $di{$_} == 0x00AD } keys %di;
+$info{$_}->{string} = '→' for grep { $di{$_} == 0x200E } keys %di;
+$info{$_}->{string} = '←' for grep { $di{$_} == 0x200F } keys %di;
+
+# convert info hashes into arrays of strings to output in display order
+for my $row (values %info) {
+       $row = [ map { $row->{$_} } qw/name category script string/ ];
+       # strip off trailing missing values (especially string may be unknown)
+       defined $row->[-1] ? last : pop @$row for 1 .. @$row;
+}
 
 # output perl code of hash
 # (assume no backslashes or curlies, so we can just q{} w/o escaping)
@@ -144,9 +171,57 @@ printf '(map {$_=>0} qw{%s}),'."\n", join(' ',
 printf "q{%s}=>[%s],\n", $_, join(',',
        $di{$_},   # original code point
        $info{$_}  # optional additional arguments
-               ? map {"'$_'"} @{ $info{$_} }{qw/name category script/},
-                       $info{$_}->{string} || ()
+               ? map {"'$_'"} @{ $info{$_} }
                : ()
 ) for sort keys %di;
 print "}\n";
 
+__END__
+
+=head1 NAME
+
+rfc1345convert - Output digraph data from RFC-1345
+
+=head1 SYNOPSIS
+
+Download and convert the digraph specification from ietf.org:
+
+    rfc1345convert > digraphs.inc.pl
+
+Test by printing the character for DO (should be a dollar sign):
+
+    perl -e'$di = do "digraphs.inc.pl"; print chr $di->{DO}->[0]'
+
+Manual specification of source retrieval:
+
+    rfc1345convert rfc1345.txt
+    curl $url | rfc1345convert -
+
+=head1 DESCRIPTION
+
+Parses the official RFC-1345 document, searching the
+'character mnemonic table' for all digraph definitions.
+If successful, Perl code is output resulting in a hash
+with character data keyed by digraph.
+Any errors and warnings are given at STDERR.
+
+The value can either be a scalar string containing another
+digraph which can be considered identical (usually inverted),
+or an array ref containing at least the resulting character's
+Unicode code point value.  If available, the following UCD data
+is appended: character name, category, script, and output string.
+For example:
+
+ +{
+   AE => [198, 'LATIN CAPITAL LETTER AE', 'Lu Xl', 'Latin'],
+   EA => 'AE',
+  }
+
+=head1 AUTHOR
+
+Mischa POSLAWSKY <perl@shiar.org>
+
+=head1 LICENSE
+
+Licensed under the GNU Affero General Public License version 3.
+