package Text::ParseWords;
-require 5.000;
-use Carp;
+use vars qw($VERSION @ISA @EXPORT $PERL_SINGLE_QUOTE);
+$VERSION = "3.21";
-require AutoLoader;
-*AUTOLOAD = \&AutoLoader::AUTOLOAD;
+require 5.000;
-require Exporter;
+use Exporter;
@ISA = qw(Exporter);
-@EXPORT = qw(shellwords quotewords);
+@EXPORT = qw(shellwords quotewords nested_quotewords parse_line);
@EXPORT_OK = qw(old_shellwords);
-=head1 NAME
-
-Text::ParseWords - parse text into an array of tokens
-
-=head1 SYNOPSIS
-
- use Text::ParseWords;
- @words = "ewords($delim, $keep, @lines);
- @words = &shellwords(@lines);
- @words = &old_shellwords(@lines);
-
-=head1 DESCRIPTION
-
-"ewords() accepts a delimiter (which can be a regular expression)
-and a list of lines and then breaks those lines up into a list of
-words ignoring delimiters that appear inside quotes.
-
-The $keep argument is a boolean flag. If true, the quotes are kept
-with each word, otherwise quotes are stripped in the splitting process.
-$keep also defines whether unprotected backslashes are retained.
-A &shellwords() replacement is included to demonstrate the new package.
-This version differs from the original in that it will _NOT_ default
-to using $_ if no arguments are given. I personally find the old behavior
-to be a mis-feature.
-
-"ewords() works by simply jamming all of @lines into a single
-string in $_ and then pulling off words a bit at a time until $_
-is exhausted.
+sub shellwords {
+ local(@lines) = @_;
+ $lines[$#lines] =~ s/\s+$//;
+ return(quotewords('\s+', 0, @lines));
+}
-=head1 AUTHORS
-Hal Pomeranz (pomeranz@netcom.com), 23 March 1994
-Basically an update and generalization of the old shellwords.pl.
-Much code shamelessly stolen from the old version (author unknown).
+sub quotewords {
+ my($delim, $keep, @lines) = @_;
+ my($line, @words, @allwords);
+
+
+ foreach $line (@lines) {
+ @words = parse_line($delim, $keep, $line);
+ return() unless (@words || !length($line));
+ push(@allwords, @words);
+ }
+ return(@allwords);
+}
-=cut
-1;
-__END__
-sub shellwords {
- local(@lines) = @_;
- $lines[$#lines] =~ s/\s+$//;
- "ewords('\s+', 0, @lines);
+sub nested_quotewords {
+ my($delim, $keep, @lines) = @_;
+ my($i, @allwords);
+
+ for ($i = 0; $i < @lines; $i++) {
+ @{$allwords[$i]} = parse_line($delim, $keep, $lines[$i]);
+ return() unless (@{$allwords[$i]} || !length($lines[$i]));
+ }
+ return(@allwords);
}
-sub quotewords {
+sub parse_line {
+ # We will be testing undef strings
+ no warnings;
+ use re 'taint'; # if it's tainted, leave it as such
-# The inner "for" loop builds up each word (or $field) one $snippet
-# at a time. A $snippet is a quoted string, a backslashed character,
-# or an unquoted string. We fall out of the "for" loop when we reach
-# the end of $_ or when we hit a delimiter. Falling out of the "for"
-# loop, we push the $field we've been building up onto the list of
-# @words we'll be returning, and then loop back and pull another word
-# off of $_.
-#
-# The first two cases inside the "for" loop deal with quoted strings.
-# The first case matches a double quoted string, removes it from $_,
-# and assigns the double quoted string to $snippet in the body of the
-# conditional. The second case handles single quoted strings. In
-# the third case we've found a quote at the current beginning of $_,
-# but it didn't match the quoted string regexps in the first two cases,
-# so it must be an unbalanced quote and we croak with an error (which can
-# be caught by eval()).
-#
-# The next case handles backslashed characters, and the next case is the
-# exit case on reaching the end of the string or finding a delimiter.
-#
-# Otherwise, we've found an unquoted thing and we pull of characters one
-# at a time until we reach something that could start another $snippet--
-# a quote of some sort, a backslash, or the delimiter. This one character
-# at a time behavior was necessary if the delimiter was going to be a
-# regexp (love to hear it if you can figure out a better way).
-
- my ($delim, $keep, @lines) = @_;
- my (@words, $snippet, $field);
-
- local $_ = join ('', @lines);
-
- while (length) {
- $field = '';
+ my($delimiter, $keep, $line) = @_;
+ my($quote, $quoted, $unquoted, $delim, $word, @pieces);
- for (;;) {
- $snippet = '';
+ while (length($line)) {
- if (s/^"([^"\\]*(\\.[^"\\]*)*)"//) {
- $snippet = $1;
- $snippet = qq|"$snippet"| if $keep;
- }
- elsif (s/^'([^'\\]*(\\.[^'\\]*)*)'//) {
- $snippet = $1;
- $snippet = "'$snippet'" if $keep;
- }
- elsif (/^["']/) {
- croak 'Unmatched quote';
- }
- elsif (s/^\\(.)//) {
- $snippet = $1;
- $snippet = "\\$snippet" if $keep;
- }
- elsif (!length || s/^$delim//) {
- last;
- }
- else {
- while (length && !(/^$delim/ || /^['"\\]/)) {
- $snippet .= substr ($_, 0, 1);
- substr($_, 0, 1) = '';
- }
- }
+ ($quote, $quoted, undef, $unquoted, $delim, undef) =
+ $line =~ m/^(["']) # a $quote
+ ((?:\\.|(?!\1)[^\\])*) # and $quoted text
+ \1 # followed by the same quote
+ ([\000-\377]*) # and the rest
+ | # --OR--
+ ^((?:\\.|[^\\"'])*?) # an $unquoted text
+ (\Z(?!\n)|(?-x:$delimiter)|(?!^)(?=["']))
+ # plus EOL, delimiter, or quote
+ ([\000-\377]*) # the rest
+ /x; # extended layout
+ return() unless( $quote || length($unquoted) || length($delim));
- $field .= $snippet;
- }
+ $line = $+;
- push @words, $field;
+ if ($keep) {
+ $quoted = "$quote$quoted$quote";
+ }
+ else {
+ $unquoted =~ s/\\(.)/$1/g;
+ if (defined $quote) {
+ $quoted =~ s/\\(.)/$1/g if ($quote eq '"');
+ $quoted =~ s/\\([\\'])/$1/g if ( $PERL_SINGLE_QUOTE && $quote eq "'");
+ }
+ }
+ $word .= defined $quote ? $quoted : $unquoted;
+
+ if (length($delim)) {
+ push(@pieces, $word);
+ push(@pieces, $delim) if ($keep eq 'delimiters');
+ undef $word;
+ }
+ if (!length($line)) {
+ push(@pieces, $word);
+ }
}
-
- return @words;
+ return(@pieces);
}
+
sub old_shellwords {
# Usage:
($snippet = $1) =~ s#\\(.)#$1#g;
}
elsif (/^"/) {
- croak "Unmatched double quote: $_";
+ return();
}
elsif (s/^'(([^'\\]|\\.)*)'//) {
($snippet = $1) =~ s#\\(.)#$1#g;
}
elsif (/^'/) {
- croak "Unmatched single quote: $_";
+ return();
}
elsif (s/^\\(.)//) {
$snippet = $1;
}
@words;
}
+
+1;
+
+__END__
+
+=head1 NAME
+
+Text::ParseWords - parse text into an array of tokens or array of arrays
+
+=head1 SYNOPSIS
+
+ use Text::ParseWords;
+ @lists = &nested_quotewords($delim, $keep, @lines);
+ @words = "ewords($delim, $keep, @lines);
+ @words = &shellwords(@lines);
+ @words = &parse_line($delim, $keep, $line);
+ @words = &old_shellwords(@lines); # DEPRECATED!
+
+=head1 DESCRIPTION
+
+The &nested_quotewords() and "ewords() functions accept a delimiter
+(which can be a regular expression)
+and a list of lines and then breaks those lines up into a list of
+words ignoring delimiters that appear inside quotes. "ewords()
+returns all of the tokens in a single long list, while &nested_quotewords()
+returns a list of token lists corresponding to the elements of @lines.
+&parse_line() does tokenizing on a single string. The &*quotewords()
+functions simply call &parse_lines(), so if you're only splitting
+one line you can call &parse_lines() directly and save a function
+call.
+
+The $keep argument is a boolean flag. If true, then the tokens are
+split on the specified delimiter, but all other characters (quotes,
+backslashes, etc.) are kept in the tokens. If $keep is false then the
+&*quotewords() functions remove all quotes and backslashes that are
+not themselves backslash-escaped or inside of single quotes (i.e.,
+"ewords() tries to interpret these characters just like the Bourne
+shell). NB: these semantics are significantly different from the
+original version of this module shipped with Perl 5.000 through 5.004.
+As an additional feature, $keep may be the keyword "delimiters" which
+causes the functions to preserve the delimiters in each string as
+tokens in the token lists, in addition to preserving quote and
+backslash characters.
+
+&shellwords() is written as a special case of "ewords(), and it
+does token parsing with whitespace as a delimiter-- similar to most
+Unix shells.
+
+=head1 EXAMPLES
+
+The sample program:
+
+ use Text::ParseWords;
+ @words = "ewords('\s+', 0, q{this is "a test" of\ quotewords \"for you});
+ $i = 0;
+ foreach (@words) {
+ print "$i: <$_>\n";
+ $i++;
+ }
+
+produces:
+
+ 0: <this>
+ 1: <is>
+ 2: <a test>
+ 3: <of quotewords>
+ 4: <"for>
+ 5: <you>
+
+demonstrating:
+
+=over 4
+
+=item 0
+
+a simple word
+
+=item 1
+
+multiple spaces are skipped because of our $delim
+
+=item 2
+
+use of quotes to include a space in a word
+
+=item 3
+
+use of a backslash to include a space in a word
+
+=item 4
+
+use of a backslash to remove the special meaning of a double-quote
+
+=item 5
+
+another simple word (note the lack of effect of the
+backslashed double-quote)
+
+=back
+
+Replacing C<"ewords('\s+', 0, q{this is...})>
+with C<&shellwords(q{this is...})>
+is a simpler way to accomplish the same thing.
+
+=head1 AUTHORS
+
+Maintainer is Hal Pomeranz <pomeranz@netcom.com>, 1994-1997 (Original
+author unknown). Much of the code for &parse_line() (including the
+primary regexp) from Joerk Behrends <jbehrends@multimediaproduzenten.de>.
+
+Examples section another documentation provided by John Heidemann
+<johnh@ISI.EDU>
+
+Bug reports, patches, and nagging provided by lots of folks-- thanks
+everybody! Special thanks to Michael Schwern <schwern@envirolink.org>
+for assuring me that a &nested_quotewords() would be useful, and to
+Jeff Friedl <jfriedl@yahoo-inc.com> for telling me not to worry about
+error-checking (sort of-- you had to be there).
+
+=cut