1 # GetOpt::Long.pm -- Universal options parsing
5 # RCS Status : $Id: GetoptLong.pl,v 2.25 2000-08-28 21:45:17+02 jv Exp $
6 # Author : Johan Vromans
7 # Created On : Tue Sep 11 15:00:12 1990
8 # Last Modified By: Johan Vromans
9 # Last Modified On: Mon Jul 31 21:21:13 2000
13 ################ Copyright ################
15 # This program is Copyright 1990,2000 by Johan Vromans.
16 # This program is free software; you can redistribute it and/or
17 # modify it under the terms of the Perl Artistic License or the
18 # GNU General Public License as published by the Free Software
19 # Foundation; either version 2 of the License, or (at your option) any
22 # This program is distributed in the hope that it will be useful,
23 # but WITHOUT ANY WARRANTY; without even the implied warranty of
24 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 # GNU General Public License for more details.
27 # If you do not have a copy of the GNU General Public License write to
28 # the Free Software Foundation, Inc., 675 Mass Ave, Cambridge,
31 ################ Module Preamble ################
38 use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);
42 @EXPORT = qw(&GetOptions $REQUIRE_ORDER $PERMUTE $RETURN_IN_ORDER);
45 use AutoLoader qw(AUTOLOAD);
48 # User visible variables.
49 use vars @EXPORT, @EXPORT_OK;
50 use vars qw($error $debug $major_version $minor_version);
51 # Deprecated visible variables.
52 use vars qw($autoabbrev $getopt_compat $ignorecase $bundling $order
54 # Official invisible variables.
55 use vars qw($genprefix $caller $gnu_compat);
59 sub config (@); # deprecated name
62 # Private subroutines.
63 sub ConfigDefaults ();
64 sub FindOption ($$$$$$$);
65 sub Croak (@); # demand loading the real Croak
67 ################ Local Variables ################
69 ################ Resident subroutines ################
71 sub ConfigDefaults () {
72 # Handle POSIX compliancy.
73 if ( defined $ENV{"POSIXLY_CORRECT"} ) {
74 $genprefix = "(--|-)";
75 $autoabbrev = 0; # no automatic abbrev of options
76 $bundling = 0; # no bundling of single letter switches
77 $getopt_compat = 0; # disallow '+' to start options
78 $order = $REQUIRE_ORDER;
81 $genprefix = "(--|-|\\+)";
82 $autoabbrev = 1; # automatic abbrev of options
83 $bundling = 0; # bundling off by default
84 $getopt_compat = 1; # allow '+' to start options
87 # Other configurable settings.
88 $debug = 0; # for debugging
89 $error = 0; # error tally
90 $ignorecase = 1; # ignore case when matching options
91 $passthrough = 0; # leave unrecognized options alone
92 $gnu_compat = 0; # require --opt=val if value is optional
97 my $pkg = shift; # package
98 my @syms = (); # symbols to import
99 my @config = (); # configuration
100 my $dest = \@syms; # symbols first
102 if ( $_ eq ':config' ) {
103 $dest = \@config; # config next
106 push (@$dest, $_); # push
108 # Hide one level and call super.
109 local $Exporter::ExportLevel = 1;
110 $pkg->SUPER::import(@syms);
112 Configure (@config) if @config;
115 ################ Initialization ################
117 # Values for $order. See GNU getopt.c for details.
118 ($REQUIRE_ORDER, $PERMUTE, $RETURN_IN_ORDER) = (0..2);
119 # Version major/minor numbers.
120 ($major_version, $minor_version) = $VERSION =~ /^(\d+)\.(\d+)/;
124 ################ OO Interface ################
126 package Getopt::Long::Parser;
128 # NOTE: The object oriented routines use $error for thread locking.
130 lock ($Getopt::Long::error) if $] >= 5.005
133 # Store a copy of the default configuration. Since ConfigDefaults has
134 # just been called, what we get from Configure is the default.
135 my $default_config = do {
137 Getopt::Long::Configure ()
142 my $class = ref($that) || $that;
145 # Register the callers package.
146 my $self = { caller => (caller)[0] };
148 bless ($self, $class);
150 # Process config attributes.
151 if ( defined $atts{config} ) {
153 my $save = Getopt::Long::Configure ($default_config, @{$atts{config}});
154 $self->{settings} = Getopt::Long::Configure ($save);
155 delete ($atts{config});
157 # Else use default config.
159 $self->{settings} = $default_config;
162 if ( %atts ) { # Oops
163 Getopt::Long::Croak(__PACKAGE__.": unhandled attributes: ".
164 join(" ", sort(keys(%atts))));
175 # Restore settings, merge new settings in.
176 my $save = Getopt::Long::Configure ($self->{settings}, @_);
178 # Restore orig config and save the new config.
179 $self->{settings} = Configure ($save);
187 # Restore config settings.
188 my $save = Getopt::Long::Configure ($self->{settings});
192 $Getopt::Long::caller = $self->{caller};
193 eval { $ret = Getopt::Long::GetOptions (@_); };
195 # Restore saved settings.
196 Getopt::Long::Configure ($save);
198 # Handle errors and return value.
203 package Getopt::Long;
205 ################ Package return ################
211 ################ AutoLoading subroutines ################
213 # RCS Status : $Id: GetoptLongAl.pl,v 2.29 2000-08-28 21:56:18+02 jv Exp $
214 # Author : Johan Vromans
215 # Created On : Fri Mar 27 11:50:30 1998
216 # Last Modified By: Johan Vromans
217 # Last Modified On: Fri Jul 28 19:12:29 2000
223 my @optionlist = @_; # local copy of the option descriptions
224 my $argend = '--'; # option list terminator
225 my %opctl = (); # table of arg.specs (long and abbrevs)
226 my %bopctl = (); # table of arg.specs (bundles)
227 my $pkg = $caller || (caller)[0]; # current context
228 # Needed if linkage is omitted.
229 my %aliases= (); # alias table
230 my @ret = (); # accum for non-options
231 my %linkage; # linkage
232 my $userlinkage; # user supplied HASH
233 my $opt; # current option
234 my $genprefix = $genprefix; # so we can call the same module many times
235 my @opctl; # the possible long option names
239 print STDERR ("GetOpt::Long $Getopt::Long::VERSION ",
240 "called from package \"$pkg\".",
242 'GetOptionsAl $Revision: 2.29 $ ',
246 "autoabbrev=$autoabbrev,".
247 "bundling=$bundling,",
248 "getopt_compat=$getopt_compat,",
249 "gnu_compat=$gnu_compat,",
252 "ignorecase=$ignorecase,",
253 "passthrough=$passthrough,",
254 "genprefix=\"$genprefix\".",
258 # Check for ref HASH as first argument.
259 # First argument may be an object. It's OK to use this as long
260 # as it is really a hash underneath.
261 $userlinkage = undef;
262 if ( ref($optionlist[0]) and
263 "$optionlist[0]" =~ /^(?:.*\=)?HASH\([^\(]*\)$/ ) {
264 $userlinkage = shift (@optionlist);
265 print STDERR ("=> user linkage: $userlinkage\n") if $debug;
268 # See if the first element of the optionlist contains option
269 # starter characters.
270 # Be careful not to interpret '<>' as option starters.
271 if ( $optionlist[0] =~ /^\W+$/
272 && !($optionlist[0] eq '<>'
274 && ref($optionlist[1])) ) {
275 $genprefix = shift (@optionlist);
276 # Turn into regexp. Needs to be parenthesized!
277 $genprefix =~ s/(\W)/\\$1/g;
278 $genprefix = "([" . $genprefix . "])";
281 # Verify correctness of optionlist.
284 while ( @optionlist > 0 ) {
285 my $opt = shift (@optionlist);
287 # Strip leading prefix so people can specify "--foo=i" if they like.
288 $opt = $+ if $opt =~ /^$genprefix+(.*)$/s;
290 if ( $opt eq '<>' ) {
291 if ( (defined $userlinkage)
292 && !(@optionlist > 0 && ref($optionlist[0]))
293 && (exists $userlinkage->{$opt})
294 && ref($userlinkage->{$opt}) ) {
295 unshift (@optionlist, $userlinkage->{$opt});
297 unless ( @optionlist > 0
298 && ref($optionlist[0]) && ref($optionlist[0]) eq 'CODE' ) {
299 $error .= "Option spec <> requires a reference to a subroutine\n";
302 $linkage{'<>'} = shift (@optionlist);
306 # Match option spec. Allow '?' as an alias only.
307 if ( $opt !~ /^((\w+[-\w]*)(\|(\?|\w[-\w]*)?)*)?([!~+]|[=:][infse][@%]?)?$/ ) {
308 $error .= "Error in option spec: \"$opt\"\n";
311 my ($o, $c, $a) = ($1, $5);
312 $c = '' unless defined $c;
314 # $linko keeps track of the primary name the user specified.
315 # This name will be used for the internal or external linkage.
316 # In other words, if the user specifies "FoO|BaR", it will
317 # match any case combinations of 'foo' and 'bar', but if a global
318 # variable needs to be set, it will be $opt_FoO in the exact case
322 if ( ! defined $o ) {
323 # empty -> '-' option
324 $opctl{$linko = $o = ''} = $c;
328 my @o = split (/\|/, $o);
330 # Force an alias if the option name is not locase.
331 $a = $o unless $o eq lc($o);
335 && ($bundling ? length($o) > 1 : 1));
338 if ( $bundling && length($_) == 1 ) {
339 $_ = lc ($_) if $ignorecase > 1;
342 warn ("Ignoring '!' modifier for short option $_\n");
343 $opctl{$_} = $bopctl{$_} = '';
346 $opctl{$_} = $bopctl{$_} = $c;
350 $_ = lc ($_) if $ignorecase;
370 # If no linkage is supplied in the @optionlist, copy it from
371 # the userlinkage if available.
372 if ( defined $userlinkage ) {
373 unless ( @optionlist > 0 && ref($optionlist[0]) ) {
374 if ( exists $userlinkage->{$linko} &&
375 ref($userlinkage->{$linko}) ) {
376 print STDERR ("=> found userlinkage for \"$linko\": ",
377 "$userlinkage->{$linko}\n")
379 unshift (@optionlist, $userlinkage->{$linko});
382 # Do nothing. Being undefined will be handled later.
388 # Copy the linkage. If omitted, link to global variable.
389 if ( @optionlist > 0 && ref($optionlist[0]) ) {
390 print STDERR ("=> link \"$linko\" to $optionlist[0]\n")
392 if ( ref($optionlist[0]) =~ /^(SCALAR|CODE)$/ ) {
393 $linkage{$linko} = shift (@optionlist);
395 elsif ( ref($optionlist[0]) =~ /^(ARRAY)$/ ) {
396 $linkage{$linko} = shift (@optionlist);
398 if $opctl{$o} ne '' and $opctl{$o} !~ /\@$/;
400 if $bundling and defined $bopctl{$o} and
401 $bopctl{$o} ne '' and $bopctl{$o} !~ /\@$/;
403 elsif ( ref($optionlist[0]) =~ /^(HASH)$/ ) {
404 $linkage{$linko} = shift (@optionlist);
406 if $opctl{$o} ne '' and $opctl{$o} !~ /\%$/;
408 if $bundling and defined $bopctl{$o} and
409 $bopctl{$o} ne '' and $bopctl{$o} !~ /\%$/;
412 $error .= "Invalid option linkage for \"$opt\"\n";
416 # Link to global $opt_XXX variable.
417 # Make sure a valid perl identifier results.
421 print STDERR ("=> link \"$linko\" to \@$pkg","::opt_$ov\n")
423 eval ("\$linkage{\$linko} = \\\@".$pkg."::opt_$ov;");
425 elsif ( $c =~ /%/ ) {
426 print STDERR ("=> link \"$linko\" to \%$pkg","::opt_$ov\n")
428 eval ("\$linkage{\$linko} = \\\%".$pkg."::opt_$ov;");
431 print STDERR ("=> link \"$linko\" to \$$pkg","::opt_$ov\n")
433 eval ("\$linkage{\$linko} = \\\$".$pkg."::opt_$ov;");
438 # Bail out if errors found.
439 die ($error) if $error;
442 # Sort the possible long option names.
443 @opctl = sort(keys (%opctl)) if $autoabbrev;
445 # Show the options tables if debugging.
449 while ( ($k,$v) = each(%opctl) ) {
450 print STDERR ($arrow, "\$opctl{\"$k\"} = \"$v\"\n");
454 while ( ($k,$v) = each(%bopctl) ) {
455 print STDERR ($arrow, "\$bopctl{\"$k\"} = \"$v\"\n");
460 # Process argument list
462 while ( $goon && @ARGV > 0 ) {
464 #### Get next argument ####
466 $opt = shift (@ARGV);
467 print STDERR ("=> option \"", $opt, "\"\n") if $debug;
469 #### Determine what we have ####
471 # Double dash is option list terminator.
472 if ( $opt eq $argend ) {
473 # Finish. Push back accumulated arguments and return.
474 unshift (@ARGV, @ret)
475 if $order == $PERMUTE;
476 return ($error == 0);
480 my $found; # success status
481 my $dsttype; # destination type ('@' or '%')
482 my $incr; # destination increment
483 my $key; # key (if hash type)
484 my $arg; # option argument
486 ($found, $opt, $arg, $dsttype, $incr, $key) =
487 FindOption ($genprefix, $argend, $opt,
488 \%opctl, \%bopctl, \@opctl, \%aliases);
492 # FindOption undefines $opt in case of errors.
493 next unless defined $opt;
495 if ( defined $arg ) {
496 if ( defined $aliases{$opt} ) {
497 print STDERR ("=> alias \"$opt\" -> \"$aliases{$opt}\"\n")
499 $opt = $aliases{$opt};
502 if ( defined $linkage{$opt} ) {
503 print STDERR ("=> ref(\$L{$opt}) -> ",
504 ref($linkage{$opt}), "\n") if $debug;
506 if ( ref($linkage{$opt}) eq 'SCALAR' ) {
508 print STDERR ("=> \$\$L{$opt} += \"$arg\"\n")
510 if ( defined ${$linkage{$opt}} ) {
511 ${$linkage{$opt}} += $arg;
514 ${$linkage{$opt}} = $arg;
518 print STDERR ("=> \$\$L{$opt} = \"$arg\"\n")
520 ${$linkage{$opt}} = $arg;
523 elsif ( ref($linkage{$opt}) eq 'ARRAY' ) {
524 print STDERR ("=> push(\@{\$L{$opt}, \"$arg\")\n")
526 push (@{$linkage{$opt}}, $arg);
528 elsif ( ref($linkage{$opt}) eq 'HASH' ) {
529 print STDERR ("=> \$\$L{$opt}->{$key} = \"$arg\"\n")
531 $linkage{$opt}->{$key} = $arg;
533 elsif ( ref($linkage{$opt}) eq 'CODE' ) {
534 print STDERR ("=> &L{$opt}(\"$opt\", \"$arg\")\n")
538 &{$linkage{$opt}}($opt, $arg);
540 print STDERR ("=> die($@)\n") if $debug && $@ ne '';
542 if ( $@ =~ /^!FINISH\b/ ) {
552 print STDERR ("Invalid REF type \"", ref($linkage{$opt}),
554 Croak ("Getopt::Long -- internal error!\n");
557 # No entry in linkage means entry in userlinkage.
558 elsif ( $dsttype eq '@' ) {
559 if ( defined $userlinkage->{$opt} ) {
560 print STDERR ("=> push(\@{\$L{$opt}}, \"$arg\")\n")
562 push (@{$userlinkage->{$opt}}, $arg);
565 print STDERR ("=>\$L{$opt} = [\"$arg\"]\n")
567 $userlinkage->{$opt} = [$arg];
570 elsif ( $dsttype eq '%' ) {
571 if ( defined $userlinkage->{$opt} ) {
572 print STDERR ("=> \$L{$opt}->{$key} = \"$arg\"\n")
574 $userlinkage->{$opt}->{$key} = $arg;
577 print STDERR ("=>\$L{$opt} = {$key => \"$arg\"}\n")
579 $userlinkage->{$opt} = {$key => $arg};
584 print STDERR ("=> \$L{$opt} += \"$arg\"\n")
586 if ( defined $userlinkage->{$opt} ) {
587 $userlinkage->{$opt} += $arg;
590 $userlinkage->{$opt} = $arg;
594 print STDERR ("=>\$L{$opt} = \"$arg\"\n") if $debug;
595 $userlinkage->{$opt} = $arg;
601 # Not an option. Save it if we $PERMUTE and don't have a <>.
602 elsif ( $order == $PERMUTE ) {
603 # Try non-options call-back.
605 if ( (defined ($cb = $linkage{'<>'})) ) {
610 print STDERR ("=> die($@)\n") if $debug && $@ ne '';
612 if ( $@ =~ /^!FINISH\b/ ) {
622 print STDERR ("=> saving \"$tryopt\" ",
623 "(not an option, may permute)\n") if $debug;
624 push (@ret, $tryopt);
629 # ...otherwise, terminate.
631 # Push this one back and exit.
632 unshift (@ARGV, $tryopt);
633 return ($error == 0);
639 if ( $order == $PERMUTE ) {
640 # Push back accumulated arguments
641 print STDERR ("=> restoring \"", join('" "', @ret), "\"\n")
642 if $debug && @ret > 0;
643 unshift (@ARGV, @ret) if @ret > 0;
646 return ($error == 0);
650 sub FindOption ($$$$$$$) {
652 # returns (1, $opt, $arg, $dsttype, $incr, $key) if okay,
653 # returns (0) otherwise.
655 my ($prefix, $argend, $opt, $opctl, $bopctl, $names, $aliases) = @_;
656 my $key; # hash key for a hash option
659 print STDERR ("=> find \"$opt\", prefix=\"$prefix\"\n") if $debug;
661 return (0) unless $opt =~ /^$prefix(.*)$/s;
666 print STDERR ("=> split \"$starter\"+\"$opt\"\n") if $debug;
668 my $optarg = undef; # value supplied with --opt=value
669 my $rest = undef; # remainder from unbundling
671 # If it is a long option, it may include the value.
672 if (($starter eq "--" || ($getopt_compat && !$bundling))
673 && $opt =~ /^([^=]+)=(.*)$/s ) {
676 print STDERR ("=> option \"", $opt,
677 "\", optarg = \"$optarg\"\n") if $debug;
682 my $tryopt = $opt; # option to try
683 my $optbl = $opctl; # table to look it up (long names)
688 if ( $bundling && $starter eq '-' ) {
689 # Unbundle single letter option.
690 $rest = substr ($tryopt, 1);
691 $tryopt = substr ($tryopt, 0, 1);
692 $tryopt = lc ($tryopt) if $ignorecase > 1;
693 print STDERR ("=> $starter$tryopt unbundled from ",
694 "$starter$tryopt$rest\n") if $debug;
695 $rest = undef unless $rest ne '';
696 $optbl = $bopctl; # look it up in the short names table
698 # If bundling == 2, long options can override bundles.
699 if ( $bundling == 2 and
701 defined ($type = $opctl->{$tryopt.$rest}) ) {
702 print STDERR ("=> $starter$tryopt rebundled to ",
703 "$starter$tryopt$rest\n") if $debug;
709 # Try auto-abbreviation.
710 elsif ( $autoabbrev ) {
711 # Downcase if allowed.
712 $tryopt = $opt = lc ($opt) if $ignorecase;
713 # Turn option name into pattern.
714 my $pat = quotemeta ($opt);
715 # Look up in option names.
716 my @hits = grep (/^$pat/, @{$names});
717 print STDERR ("=> ", scalar(@hits), " hits (@hits) with \"$pat\" ",
718 "out of ", scalar(@{$names}), "\n") if $debug;
720 # Check for ambiguous results.
721 unless ( (@hits <= 1) || (grep ($_ eq $opt, @hits) == 1) ) {
722 # See if all matches are for the same option.
725 $_ = $aliases->{$_} if defined $aliases->{$_};
728 # Now see if it really is ambiguous.
729 unless ( keys(%hit) == 1 ) {
730 return (0) if $passthrough;
731 warn ("Option ", $opt, " is ambiguous (",
732 join(", ", @hits), ")\n");
735 return (1, $opt,$arg,$dsttype,$incr,$key);
740 # Complete the option name, if appropriate.
741 if ( @hits == 1 && $hits[0] ne $opt ) {
743 $tryopt = lc ($tryopt) if $ignorecase;
744 print STDERR ("=> option \"$opt\" -> \"$tryopt\"\n")
749 # Map to all lowercase if ignoring case.
750 elsif ( $ignorecase ) {
754 # Check validity by fetching the info.
755 $type = $optbl->{$tryopt} unless defined $type;
756 unless ( defined $type ) {
757 return (0) if $passthrough;
758 warn ("Unknown option: ", $opt, "\n");
760 return (1, $opt,$arg,$dsttype,$incr,$key);
764 print STDERR ("=> found \"$type\" for \"", $opt, "\"\n") if $debug;
766 #### Determine argument status ####
768 # If it is an option w/o argument, we're almost finished with it.
769 if ( $type eq '' || $type eq '!' || $type eq '+' ) {
770 if ( defined $optarg ) {
771 return (0) if $passthrough;
772 warn ("Option ", $opt, " does not take an argument\n");
776 elsif ( $type eq '' || $type eq '+' ) {
777 $arg = 1; # supply explicit value
778 $incr = $type eq '+';
781 substr ($opt, 0, 2) = ''; # strip NO prefix
782 $arg = 0; # supply explicit value
784 unshift (@ARGV, $starter.$rest) if defined $rest;
785 return (1, $opt,$arg,$dsttype,$incr,$key);
788 # Get mandatory status and type info.
790 ($mand, $type, $dsttype, $key) = $type =~ /^(.)(.)([@%]?)$/;
792 # Check if there is an option argument available.
794 return (1, $opt, $optarg, $dsttype, $incr, $key)
796 return (1, $opt, $type eq "s" ? '' : 0, $dsttype, $incr, $key)
800 # Check if there is an option argument available.
803 : !(defined $rest || @ARGV > 0) ) {
804 # Complain if this option needs an argument.
805 if ( $mand eq "=" ) {
806 return (0) if $passthrough;
807 warn ("Option ", $opt, " requires an argument\n");
811 return (1, $opt, $type eq "s" ? '' : 0, $dsttype, $incr, $key);
814 # Get (possibly optional) argument.
815 $arg = (defined $rest ? $rest
816 : (defined $optarg ? $optarg : shift (@ARGV)));
818 # Get key if this is a "name=value" pair for a hash option.
820 if ($dsttype eq '%' && defined $arg) {
821 ($key, $arg) = ($arg =~ /^([^=]*)=(.*)$/s) ? ($1, $2) : ($arg, 1);
824 #### Check if the argument is valid for this option ####
826 if ( $type eq "s" ) { # string
827 # A mandatory string takes anything.
828 return (1, $opt,$arg,$dsttype,$incr,$key) if $mand eq "=";
830 # An optional string takes almost anything.
831 return (1, $opt,$arg,$dsttype,$incr,$key)
832 if defined $optarg || defined $rest;
833 return (1, $opt,$arg,$dsttype,$incr,$key) if $arg eq "-"; # ??
835 # Check for option or option list terminator.
836 if ($arg eq $argend ||
837 $arg =~ /^$prefix.+/) {
839 unshift (@ARGV, $arg);
840 # Supply empty value.
845 elsif ( $type eq "n" || $type eq "i" ) { # numeric/integer
846 if ( $bundling && defined $rest && $rest =~ /^([-+]?[0-9]+)(.*)$/s ) {
849 unshift (@ARGV, $starter.$rest) if defined $rest && $rest ne '';
851 elsif ( $arg !~ /^[-+]?[0-9]+$/ ) {
852 if ( defined $optarg || $mand eq "=" ) {
853 if ( $passthrough ) {
854 unshift (@ARGV, defined $rest ? $starter.$rest : $arg)
855 unless defined $optarg;
858 warn ("Value \"", $arg, "\" invalid for option ",
859 $opt, " (number expected)\n");
863 unshift (@ARGV, $starter.$rest) if defined $rest;
867 unshift (@ARGV, defined $rest ? $starter.$rest : $arg);
868 # Supply default value.
874 elsif ( $type eq "f" ) { # real number, int is also ok
875 # We require at least one digit before a point or 'e',
876 # and at least one digit following the point and 'e'.
878 if ( $bundling && defined $rest &&
879 $rest =~ /^([-+]?[0-9]+(\.[0-9]+)?([eE][-+]?[0-9]+)?)(.*)$/s ) {
882 unshift (@ARGV, $starter.$rest) if defined $rest && $rest ne '';
884 elsif ( $arg !~ /^[-+]?[0-9.]+(\.[0-9]+)?([eE][-+]?[0-9]+)?$/ ) {
885 if ( defined $optarg || $mand eq "=" ) {
886 if ( $passthrough ) {
887 unshift (@ARGV, defined $rest ? $starter.$rest : $arg)
888 unless defined $optarg;
891 warn ("Value \"", $arg, "\" invalid for option ",
892 $opt, " (real number expected)\n");
896 unshift (@ARGV, $starter.$rest) if defined $rest;
900 unshift (@ARGV, defined $rest ? $starter.$rest : $arg);
901 # Supply default value.
907 Croak ("GetOpt::Long internal error (Can't happen)\n");
909 return (1, $opt, $arg, $dsttype, $incr, $key);
912 # Getopt::Long Configuration.
917 [ $error, $debug, $major_version, $minor_version,
918 $autoabbrev, $getopt_compat, $ignorecase, $bundling, $order,
919 $gnu_compat, $passthrough, $genprefix ];
921 if ( ref($options[0]) eq 'ARRAY' ) {
922 ( $error, $debug, $major_version, $minor_version,
923 $autoabbrev, $getopt_compat, $ignorecase, $bundling, $order,
924 $gnu_compat, $passthrough, $genprefix ) = @{shift(@options)};
928 foreach $opt ( @options ) {
931 if ( $try =~ /^no_?(.*)$/s ) {
935 if ( ($try eq 'default' or $try eq 'defaults') && $action ) {
938 elsif ( ($try eq 'posix_default' or $try eq 'posix_defaults') ) {
939 local $ENV{POSIXLY_CORRECT};
940 $ENV{POSIXLY_CORRECT} = 1 if $action;
943 elsif ( $try eq 'auto_abbrev' or $try eq 'autoabbrev' ) {
944 $autoabbrev = $action;
946 elsif ( $try eq 'getopt_compat' ) {
947 $getopt_compat = $action;
949 elsif ( $try eq 'gnu_getopt' ) {
957 elsif ( $try eq 'gnu_compat' ) {
958 $gnu_compat = $action;
960 elsif ( $try eq 'ignorecase' or $try eq 'ignore_case' ) {
961 $ignorecase = $action;
963 elsif ( $try eq 'ignore_case_always' ) {
964 $ignorecase = $action ? 2 : 0;
966 elsif ( $try eq 'bundling' ) {
969 elsif ( $try eq 'bundling_override' ) {
970 $bundling = $action ? 2 : 0;
972 elsif ( $try eq 'require_order' ) {
973 $order = $action ? $REQUIRE_ORDER : $PERMUTE;
975 elsif ( $try eq 'permute' ) {
976 $order = $action ? $PERMUTE : $REQUIRE_ORDER;
978 elsif ( $try eq 'pass_through' or $try eq 'passthrough' ) {
979 $passthrough = $action;
981 elsif ( $try =~ /^prefix=(.+)$/ && $action ) {
983 # Turn into regexp. Needs to be parenthesized!
984 $genprefix = "(" . quotemeta($genprefix) . ")";
985 eval { '' =~ /$genprefix/; };
986 Croak ("Getopt::Long: invalid pattern \"$genprefix\"") if $@;
988 elsif ( $try =~ /^prefix_pattern=(.+)$/ && $action ) {
990 # Parenthesize if needed.
991 $genprefix = "(" . $genprefix . ")"
992 unless $genprefix =~ /^\(.*\)$/;
993 eval { '' =~ /$genprefix/; };
994 Croak ("Getopt::Long: invalid pattern \"$genprefix\"") if $@;
996 elsif ( $try eq 'debug' ) {
1000 Croak ("Getopt::Long: unknown config parameter \"$opt\"")
1011 # To prevent Carp from being loaded unnecessarily.
1014 $Carp::CarpLevel = 1;
1018 ################ Documentation ################
1022 Getopt::Long - Extended processing of command line options
1027 $result = GetOptions (...option-descriptions...);
1031 The Getopt::Long module implements an extended getopt function called
1032 GetOptions(). This function adheres to the POSIX syntax for command
1033 line options, with GNU extensions. In general, this means that options
1034 have long names instead of single letters, and are introduced with a
1035 double dash "--". Support for bundling of command line options, as was
1036 the case with the more traditional single-letter approach, is provided
1037 but not enabled by default.
1039 =head1 Command Line Options, an Introduction
1041 Command line operated programs traditionally take their arguments from
1042 the command line, for example filenames or other information that the
1043 program needs to know. Besides arguments, these programs often take
1044 command line I<options> as well. Options are not necessary for the
1045 program to work, hence the name 'option', but are used to modify its
1046 default behaviour. For example, a program could do its job quietly,
1047 but with a suitable option it could provide verbose information about
1050 Command line options come in several flavours. Historically, they are
1051 preceded by a single dash C<->, and consist of a single letter.
1055 Usually, these single-character options can be bundled:
1059 Options can have values, the value is placed after the option
1060 character. Sometimes with whitespace in between, sometimes not:
1064 Due to the very cryptic nature of these options, another style was
1065 developed that used long names. So instead of a cryptic C<-l> one
1066 could use the more descriptive C<--long>. To distinguish between a
1067 bundle of single-character options and a long one, two dashes are used
1068 to precede the option name. Early implementations of long options used
1069 a plus C<+> instead. Also, option values could be specified either
1078 The C<+> form is now obsolete and strongly deprecated.
1080 =head1 Getting Started with Getopt::Long
1082 Getopt::Long is the Perl5 successor of C<newgetopt.pl>. This was
1083 the first Perl module that provided support for handling the new style
1084 of command line options, hence the name Getopt::Long. This module
1085 also supports single-character options and bundling. In this case, the
1086 options are restricted to alphabetic characters only, and the
1087 characters C<?> and C<->.
1089 To use Getopt::Long from a Perl program, you must include the
1090 following line in your Perl program:
1094 This will load the core of the Getopt::Long module and prepare your
1095 program for using it. Most of the actual Getopt::Long code is not
1096 loaded until you really call one of its functions.
1098 In the default configuration, options names may be abbreviated to
1099 uniqueness, case does not matter, and a single dash is sufficient,
1100 even for long option names. Also, options may be placed between
1101 non-option arguments. See L<Configuring Getopt::Long> for more
1102 details on how to configure Getopt::Long.
1104 =head2 Simple options
1106 The most simple options are the ones that take no values. Their mere
1107 presence on the command line enables the option. Popular examples are:
1109 --all --verbose --quiet --debug
1111 Handling simple options is straightforward:
1113 my $verbose = ''; # option variable with default value (false)
1114 my $all = ''; # option variable with default value (false)
1115 GetOptions ('verbose' => \$verbose, 'all' => \$all);
1117 The call to GetOptions() parses the command line arguments that are
1118 present in C<@ARGV> and sets the option variable to the value C<1> if
1119 the option did occur on the command line. Otherwise, the option
1120 variable is not touched. Setting the option value to true is often
1121 called I<enabling> the option.
1123 The option name as specified to the GetOptions() function is called
1124 the option I<specification>. Later we'll see that this specification
1125 can contain more than just the option name. The reference to the
1126 variable is called the option I<destination>.
1128 GetOptions() will return a true value if the command line could be
1129 processed successfully. Otherwise, it will write error messages to
1130 STDERR, and return a false result.
1132 =head2 A little bit less simple options
1134 Getopt::Long supports two useful variants of simple options:
1135 I<negatable> options and I<incremental> options.
1137 A negatable option is specified with a exclamation mark C<!> after the
1140 my $verbose = ''; # option variable with default value (false)
1141 GetOptions ('verbose!' => \$verbose);
1143 Now, using C<--verbose> on the command line will enable C<$verbose>,
1144 as expected. But it is also allowed to use C<--noverbose>, which will
1145 disable C<$verbose> by setting its value to C<0>. Using a suitable
1146 default value, the program can find out whether C<$verbose> is false
1147 by default, or disabled by using C<--noverbose>.
1149 An incremental option is specified with a plus C<+> after the
1152 my $verbose = ''; # option variable with default value (false)
1153 GetOptions ('verbose+' => \$verbose);
1155 Using C<--verbose> on the command line will increment the value of
1156 C<$verbose>. This way the program can keep track of how many times the
1157 option occurred on the command line. For example, each occurrence of
1158 C<--verbose> could increase the verbosity level of the program.
1160 =head2 Mixing command line option with other arguments
1162 Usually programs take command line options as well as other arguments,
1163 for example, file names. It is good practice to always specify the
1164 options first, and the other arguments last. Getopt::Long will,
1165 however, allow the options and arguments to be mixed and 'filter out'
1166 all the options before passing the rest of the arguments to the
1167 program. To stop Getopt::Long from processing further arguments,
1168 insert a double dash C<--> on the command line:
1172 In this example, C<--all> will I<not> be treated as an option, but
1173 passed to the program unharmed, in C<@ARGV>.
1175 =head2 Options with values
1177 For options that take values it must be specified whether the option
1178 value is required or not, and what kind of value the option expects.
1180 Three kinds of values are supported: integer numbers, floating point
1181 numbers, and strings.
1183 If the option value is required, Getopt::Long will take the
1184 command line argument that follows the option and assign this to the
1185 option variable. If, however, the option value is specified as
1186 optional, this will only be done if that value does not look like a
1187 valid command line option itself.
1189 my $tag = ''; # option variable with default value
1190 GetOptions ('tag=s' => \$tag);
1192 In the option specification, the option name is followed by an equals
1193 sign C<=> and the letter C<s>. The equals sign indicates that this
1194 option requires a value. The letter C<s> indicates that this value is
1195 an arbitrary string. Other possible value types are C<i> for integer
1196 values, and C<f> for floating point values. Using a colon C<:> instead
1197 of the equals sign indicates that the option value is optional. In
1198 this case, if no suitable value is supplied, string valued options get
1199 an empty string C<''> assigned, while numeric options are set to C<0>.
1201 =head2 Options with multiple values
1203 Options sometimes take several values. For example, a program could
1204 use multiple directories to search for library files:
1206 --library lib/stdlib --library lib/extlib
1208 To accomplish this behaviour, simply specify an array reference as the
1209 destination for the option:
1212 GetOptions ("library=s" => \@libfiles);
1214 Used with the example above, C<@libfiles> would contain two strings
1215 upon completion: C<"lib/srdlib"> and C<"lib/extlib">, in that order.
1216 It is also possible to specify that only integer or floating point
1217 numbers are acceptible values.
1219 Often it is useful to allow comma-separated lists of values as well as
1220 multiple occurrences of the options. This is easy using Perl's split()
1221 and join() operators:
1224 GetOptions ("library=s" => \@libfiles);
1225 @libfiles = split(/,/,join(',',@libfiles));
1227 Of course, it is important to choose the right separator string for
1230 =head2 Options with hash values
1232 If the option destination is a reference to a hash, the option will
1233 take, as value, strings of the form I<key>C<=>I<value>. The value will
1234 be stored with the specified key in the hash.
1237 GetOptions ("define=s" => \%defines);
1239 When used with command line options:
1241 --define os=linux --define vendor=redhat
1243 the hash C<%defines> will contain two keys, C<"os"> with value
1244 C<"linux> and C<"vendor"> with value C<"redhat">.
1245 It is also possible to specify that only integer or floating point
1246 numbers are acceptible values. The keys are always taken to be strings.
1248 =head2 User-defined subroutines to handle options
1250 Ultimate control over what should be done when (actually: each time)
1251 an option is encountered on the command line can be achieved by
1252 designating a reference to a subroutine (or an anonymous subroutine)
1253 as the option destination. When GetOptions() encounters the option, it
1254 will call the subroutine with two arguments: the name of the option,
1255 and the value to be assigned. It is up to the subroutine to store the
1256 value, or do whatever it thinks is appropriate.
1258 A trivial application of this mechanism is to implement options that
1259 are related to each other. For example:
1261 my $verbose = ''; # option variable with default value (false)
1262 GetOptions ('verbose' => \$verbose,
1263 'quiet' => sub { $verbose = 0 });
1265 Here C<--verbose> and C<--quiet> control the same variable
1266 C<$verbose>, but with opposite values.
1268 If the subroutine needs to signal an error, it should call die() with
1269 the desired error message as its argument. GetOptions() will catch the
1270 die(), issue the error message, and record that an error result must
1271 be returned upon completion.
1273 If the text of the error message starts with an exclamantion mark C<!>
1274 it is interpreted specially by GetOptions(). There is currently one
1275 special command implemented: C<die("!FINISH")> will cause GetOptions()
1276 to stop processing options, as if it encountered a double dash C<-->.
1278 =head2 Options with multiple names
1280 Often it is user friendly to supply alternate mnemonic names for
1281 options. For example C<--height> could be an alternate name for
1282 C<--length>. Alternate names can be included in the option
1283 specification, separated by vertical bar C<|> characters. To implement
1286 GetOptions ('length|height=f' => \$length);
1288 The first name is called the I<primary> name, the other names are
1291 Multiple alternate names are possible.
1293 =head2 Case and abbreviations
1295 Without additional configuration, GetOptions() will ignore the case of
1296 option names, and allow the options to be abbreviated to uniqueness.
1298 GetOptions ('length|height=f' => \$length, "head" => \$head);
1300 This call will allow C<--l> and C<--L> for the length option, but
1301 requires a least C<--hea> and C<--hei> for the head and height options.
1303 =head2 Summary of Option Specifications
1305 Each option specifier consists of two parts: the name specification
1306 and the argument specification.
1308 The name specification contains the name of the option, optionally
1309 followed by a list of alternative names separated by vertical bar
1312 length option name is "length"
1313 length|size|l name is "length", aliases are "size" and "l"
1315 The argument specification is optional. If omitted, the option is
1316 considered boolean, a value of 1 will be assigned when the option is
1317 used on the command line.
1319 The argument specification can be
1325 The option does not take an argument and may be negated, i.e. prefixed
1326 by "no". E.g. C<"foo!"> will allow C<--foo> (a value of 1 will be
1327 assigned) and C<--nofoo> (a value of 0 will be assigned). If the
1328 option has aliases, this applies to the aliases as well.
1330 Using negation on a single letter option when bundling is in effect is
1331 pointless and will result in a warning.
1335 The option does not take an argument and will be incremented by 1
1336 every time it appears on the command line. E.g. C<"more+">, when used
1337 with C<--more --more --more>, will increment the value three times,
1338 resulting in a value of 3 (provided it was 0 or undefined at first).
1340 The C<+> specifier is ignored if the option destination is not a scalar.
1342 =item = I<type> [ I<desttype> ]
1344 The option requires an argument of the given type. Supported types
1351 String. An arbitrary sequence of characters. It is valid for the
1352 argument to start with C<-> or C<-->.
1356 Integer. An optional leading plus or minus sign, followed by a
1361 Real number. For example C<3.14>, C<-6.23E24> and so on.
1365 The I<desttype> can be C<@> or C<%> to specify that the option is
1366 list or a hash valued. This is only needed when the destination for
1367 the option value is not otherwise specified. It should be omitted when
1370 =item : I<type> [ I<desttype> ]
1372 Like C<=>, but designates the argument as optional.
1373 If omitted, an empty string will be assigned to string values options,
1374 and the value zero to numeric options.
1376 Note that if a string argument starts with C<-> or C<-->, it will be
1377 considered an option on itself.
1381 =head1 Advanced Possibilities
1383 =head2 Object oriented interface
1385 Getopt::Long can be used in an object oriented way as well:
1388 $p = new Getopt::Long::Parser;
1389 $p->configure(...configuration options...);
1390 if ($p->getoptions(...options descriptions...)) ...
1392 Configuration options can be passed to the constructor:
1394 $p = new Getopt::Long::Parser
1395 config => [...configuration options...];
1397 For thread safety, each method call will acquire an exclusive lock to
1398 the Getopt::Long module. So don't call these methods from a callback
1401 =head2 Documentation and help texts
1403 Getopt::Long encourages the use of Pod::Usage to produce help
1404 messages. For example:
1412 GetOptions('help|?' => \$help, man => \$man) or pod2usage(2);
1413 pod2usage(1) if $help;
1414 pod2usage(-exitstatus => 0, -verbose => 2) if $man;
1420 sample - Using GetOpt::Long and Pod::Usage
1424 sample [options] [file ...]
1427 -help brief help message
1428 -man full documentation
1436 Print a brief help message and exits.
1440 Prints the manual page and exits.
1446 B<This program> will read the given input file(s) and do someting
1447 useful with the contents thereof.
1451 See L<Pod::Usage> for details.
1453 =head2 Storing options in a hash
1455 Sometimes, for example when there are a lot of options, having a
1456 separate variable for each of them can be cumbersome. GetOptions()
1457 supports, as an alternative mechanism, storing options in a hash.
1459 To obtain this, a reference to a hash must be passed I<as the first
1460 argument> to GetOptions(). For each option that is specified on the
1461 command line, the option value will be stored in the hash with the
1462 option name as key. Options that are not actually used on the command
1463 line will not be put in the hash, on other words,
1464 C<exists($h{option})> (or defined()) can be used to test if an option
1465 was used. The drawback is that warnings will be issued if the program
1466 runs under C<use strict> and uses C<$h{option}> without testing with
1467 exists() or defined() first.
1470 GetOptions (\%h, 'length=i'); # will store in $h{length}
1472 For options that take list or hash values, it is necessary to indicate
1473 this by appending an C<@> or C<%> sign after the type:
1475 GetOptions (\%h, 'colours=s@'); # will push to @{$h{colours}}
1477 To make things more complicated, the hash may contain references to
1478 the actual destinations, for example:
1481 my %h = ('length' => \$len);
1482 GetOptions (\%h, 'length=i'); # will store in $len
1484 This example is fully equivalent with:
1487 GetOptions ('length=i' => \$len); # will store in $len
1489 Any mixture is possible. For example, the most frequently used options
1490 could be stored in variables while all other options get stored in the
1493 my $verbose = 0; # frequently referred
1494 my $debug = 0; # frequently referred
1495 my %h = ('verbose' => \$verbose, 'debug' => \$debug);
1496 GetOptions (\%h, 'verbose', 'debug', 'filter', 'size=i');
1497 if ( $verbose ) { ... }
1498 if ( exists $h{filter} ) { ... option 'filter' was specified ... }
1502 With bundling it is possible to set several single-character options
1503 at once. For example if C<a>, C<v> and C<x> are all valid options,
1507 would set all three.
1509 Getopt::Long supports two levels of bundling. To enable bundling, a
1510 call to Getopt::Long::Configure is required.
1512 The first level of bundling can be enabled with:
1514 Getopt::Long::Configure ("bundling");
1516 Configured this way, single-character options can be bundled but long
1517 options B<must> always start with a double dash C<--> to avoid
1518 abiguity. For example, when C<vax>, C<a>, C<v> and C<x> are all valid
1523 would set C<a>, C<v> and C<x>, but
1529 The second level of bundling lifts this restriction. It can be enabled
1532 Getopt::Long::Configure ("bundling_override");
1534 Now, C<-vax> would set the option C<vax>.
1536 When any level of bundling is enabled, option values may be inserted
1537 in the bundle. For example:
1545 When configured for bundling, single-character options are matched
1546 case sensitive while long options are matched case insensitive. To
1547 have the single-character options matched case insensitive as well,
1550 Getopt::Long::Configure ("bundling", "ignorecase_always");
1552 It goes without saying that bundling can be quite confusing.
1554 =head2 The lonesome dash
1556 Some applications require the option C<-> (that's a lone dash). This
1557 can be achieved by adding an option specification with an empty name:
1559 GetOptions ('' => \$stdio);
1561 A lone dash on the command line will now be legal, and set options
1564 =head2 Argument call-back
1566 A special option 'name' C<<>> can be used to designate a subroutine
1567 to handle non-option arguments. When GetOptions() encounters an
1568 argument that does not look like an option, it will immediately call this
1569 subroutine and passes it the argument as a parameter.
1575 GetOptions ('width=i' => \$width, '<>' => \&process);
1577 When applied to the following command line:
1579 arg1 --width=72 arg2 --width=60 arg3
1582 C<process("arg1")> while C<$width> is C<80>,
1583 C<process("arg2")> while C<$width> is C<72>, and
1584 C<process("arg3")> while C<$width> is C<60>.
1586 This feature requires configuration option B<permute>, see section
1587 L<Configuring Getopt::Long>.
1590 =head1 Configuring Getopt::Long
1592 Getopt::Long can be configured by calling subroutine
1593 Getopt::Long::Configure(). This subroutine takes a list of quoted
1594 strings, each specifying a configuration option to be enabled, e.g.
1595 C<ignore_case>, or disabled, e.g. C<no_ignore_case>. Case does not
1596 matter. Multiple calls to Configure() are possible.
1598 Alternatively, as of version 2.24, the configuration options may be
1599 passed together with the C<use> statement:
1601 use Getopt::Long qw(:config no_ignore_case bundling);
1603 The following options are available:
1609 This option causes all configuration options to be reset to their
1614 This option causes all configuration options to be reset to their
1615 default values as if the environment variable POSIXLY_CORRECT had
1620 Allow option names to be abbreviated to uniqueness.
1621 Default is enabled unless environment variable
1622 POSIXLY_CORRECT has been set, in which case C<auto_abbrev> is disabled.
1626 Allow C<+> to start options.
1627 Default is enabled unless environment variable
1628 POSIXLY_CORRECT has been set, in which case C<getopt_compat> is disabled.
1632 C<gnu_compat> controls whether C<--opt=> is allowed, and what it should
1633 do. Without C<gnu_compat>, C<--opt=> gives an error. With C<gnu_compat>,
1634 C<--opt=> will give option C<opt> and empty value.
1635 This is the way GNU getopt_long() does it.
1639 This is a short way of setting C<gnu_compat> C<bundling> C<permute>
1640 C<no_getopt_compat>. With C<gnu_getopt>, command line handling should be
1641 fully compatible with GNU getopt_long().
1645 Whether command line arguments are allowed to be mixed with options.
1646 Default is disabled unless environment variable
1647 POSIXLY_CORRECT has been set, in which case C<require_order> is enabled.
1649 See also C<permute>, which is the opposite of C<require_order>.
1653 Whether command line arguments are allowed to be mixed with options.
1654 Default is enabled unless environment variable
1655 POSIXLY_CORRECT has been set, in which case C<permute> is disabled.
1656 Note that C<permute> is the opposite of C<require_order>.
1658 If C<permute> is enabled, this means that
1660 --foo arg1 --bar arg2 arg3
1664 --foo --bar arg1 arg2 arg3
1666 If an argument call-back routine is specified, C<@ARGV> will always be
1667 empty upon succesful return of GetOptions() since all options have been
1668 processed. The only exception is when C<--> is used:
1670 --foo arg1 --bar arg2 -- arg3
1672 will call the call-back routine for arg1 and arg2, and terminate
1673 GetOptions() leaving C<"arg2"> in C<@ARGV>.
1675 If C<require_order> is enabled, options processing
1676 terminates when the first non-option is encountered.
1678 --foo arg1 --bar arg2 arg3
1682 --foo -- arg1 --bar arg2 arg3
1684 =item bundling (default: disabled)
1686 Enabling this option will allow single-character options to be bundled.
1687 To distinguish bundles from long option names, long options I<must> be
1688 introduced with C<--> and single-character options (and bundles) with
1691 Note: disabling C<bundling> also disables C<bundling_override>.
1693 =item bundling_override (default: disabled)
1695 If C<bundling_override> is enabled, bundling is enabled as with
1696 C<bundling> but now long option names override option bundles.
1698 Note: disabling C<bundling_override> also disables C<bundling>.
1700 B<Note:> Using option bundling can easily lead to unexpected results,
1701 especially when mixing long options and bundles. Caveat emptor.
1703 =item ignore_case (default: enabled)
1705 If enabled, case is ignored when matching long option names. Single
1706 character options will be treated case-sensitive.
1708 Note: disabling C<ignore_case> also disables C<ignore_case_always>.
1710 =item ignore_case_always (default: disabled)
1712 When bundling is in effect, case is ignored on single-character
1715 Note: disabling C<ignore_case_always> also disables C<ignore_case>.
1717 =item pass_through (default: disabled)
1719 Options that are unknown, ambiguous or supplied with an invalid option
1720 value are passed through in C<@ARGV> instead of being flagged as
1721 errors. This makes it possible to write wrapper scripts that process
1722 only part of the user supplied command line arguments, and pass the
1723 remaining options to some other program.
1725 This can be very confusing, especially when C<permute> is also enabled.
1729 The string that starts options. If a constant string is not
1730 sufficient, see C<prefix_pattern>.
1732 =item prefix_pattern
1734 A Perl pattern that identifies the strings that introduce options.
1735 Default is C<(--|-|\+)> unless environment variable
1736 POSIXLY_CORRECT has been set, in which case it is C<(--|-)>.
1738 =item debug (default: disabled)
1740 Enable debugging output.
1744 =head1 Return values and Errors
1746 Configuration errors and errors in the option definitions are
1747 signalled using die() and will terminate the calling program unless
1748 the call to Getopt::Long::GetOptions() was embedded in C<eval { ...
1749 }>, or die() was trapped using C<$SIG{__DIE__}>.
1751 GetOptions returns true to indicate success.
1752 It returns false when the function detected one or more errors during
1753 option parsing. These errors are signalled using warn() and can be
1754 trapped with C<$SIG{__WARN__}>.
1756 Errors that can't happen are signalled using Carp::croak().
1760 The earliest development of C<newgetopt.pl> started in 1990, with Perl
1761 version 4. As a result, its development, and the development of
1762 Getopt::Long, has gone through several stages. Since backward
1763 compatibility has always been extremely important, the current version
1764 of Getopt::Long still supports a lot of constructs that nowadays are
1765 no longer necessary or otherwise unwanted. This section describes
1766 briefly some of these 'features'.
1768 =head2 Default destinations
1770 When no destination is specified for an option, GetOptions will store
1771 the resultant value in a global variable named C<opt_>I<XXX>, where
1772 I<XXX> is the primary name of this option. When a progam executes
1773 under C<use strict> (recommended), these variables must be
1774 pre-declared with our() or C<use vars>.
1776 our $opt_length = 0;
1777 GetOptions ('length=i'); # will store in $opt_length
1779 To yield a usable Perl variable, characters that are not part of the
1780 syntax for variables are translated to underscores. For example,
1781 C<--fpp-struct-return> will set the variable
1782 C<$opt_fpp_struct_return>. Note that this variable resides in the
1783 namespace of the calling program, not necessarily C<main>. For
1786 GetOptions ("size=i", "sizes=i@");
1788 with command line "-size 10 -sizes 24 -sizes 48" will perform the
1789 equivalent of the assignments
1792 @opt_sizes = (24, 48);
1794 =head2 Alternative option starters
1796 A string of alternative option starter characters may be passed as the
1797 first argument (or the first argument after a leading hash reference
1801 GetOptions ('/', 'length=i' => $len);
1803 Now the command line may look like:
1807 Note that to terminate options processing still requires a double dash
1810 GetOptions() will not interpret a leading C<< "<>" >> as option starters
1811 if the next argument is a reference. To force C<< "<" >> and C<< ">" >> as
1812 option starters, use C<< "><" >>. Confusing? Well, B<using a starter
1813 argument is strongly deprecated> anyway.
1815 =head2 Configuration variables
1817 Previous versions of Getopt::Long used variables for the purpose of
1818 configuring. Although manipulating these variables still work, it is
1819 strongly encouraged to use the C<Configure> routine that was introduced
1820 in version 2.17. Besides, it is much easier.
1822 =head1 Trouble Shooting
1824 =head2 Warning: Ignoring '!' modifier for short option
1826 This warning is issued when the '!' modifier is applied to a short
1827 (one-character) option and bundling is in effect. E.g.,
1829 Getopt::Long::Configure("bundling");
1830 GetOptions("foo|f!" => \$foo);
1832 Note that older Getopt::Long versions did not issue a warning, because
1833 the '!' modifier was applied to the first name only. This bug was
1836 Solution: separate the long and short names and apply the '!' to the
1837 long names only, e.g.,
1839 GetOptions("foo!" => \$foo, "f" => \$foo);
1841 =head2 GetOptions does not return a false result when an option is not supplied
1843 That's why they're called 'options'.
1847 Johan Vromans <jvromans@squirrel.nl>
1849 =head1 COPYRIGHT AND DISCLAIMER
1851 This program is Copyright 2000,1990 by Johan Vromans.
1852 This program is free software; you can redistribute it and/or
1853 modify it under the terms of the Perl Artistic License or the
1854 GNU General Public License as published by the Free Software
1855 Foundation; either version 2 of the License, or (at your option) any
1858 This program is distributed in the hope that it will be useful,
1859 but WITHOUT ANY WARRANTY; without even the implied warranty of
1860 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1861 GNU General Public License for more details.
1863 If you do not have a copy of the GNU General Public License write to
1864 the Free Software Foundation, Inc., 675 Mass Ave, Cambridge,
1871 # eval: (load-file "pod.el")