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package Text::ParseWords; | |
use strict; | |
require 5.006; | |
our $VERSION = "3.30"; | |
use Exporter; | |
our @ISA = qw(Exporter); | |
our @EXPORT = qw(shellwords quotewords nested_quotewords parse_line); | |
our @EXPORT_OK = qw(old_shellwords); | |
our $PERL_SINGLE_QUOTE; | |
sub shellwords { | |
my (@lines) = @_; | |
my @allwords; | |
foreach my $line (@lines) { | |
$line =~ s/^\s+//; | |
my @words = parse_line('\s+', 0, $line); | |
pop @words if (@words and !defined $words[-1]); | |
return() unless (@words || !length($line)); | |
push(@allwords, @words); | |
} | |
return(@allwords); | |
} | |
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); | |
} | |
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 parse_line { | |
my($delimiter, $keep, $line) = @_; | |
my($word, @pieces); | |
no warnings 'uninitialized'; # we will be testing undef strings | |
while (length($line)) { | |
# This pattern is optimised to be stack conservative on older perls. | |
# Do not refactor without being careful and testing it on very long strings. | |
# See Perl bug #42980 for an example of a stack busting input. | |
$line =~ s/^ | |
(?: | |
# double quoted string | |
(") # $quote | |
((?>[^\\"]*(?:\\.[^\\"]*)*))" # $quoted | |
| # --OR-- | |
# singe quoted string | |
(') # $quote | |
((?>[^\\']*(?:\\.[^\\']*)*))' # $quoted | |
| # --OR-- | |
# unquoted string | |
( # $unquoted | |
(?:\\.|[^\\"'])*? | |
) | |
# followed by | |
( # $delim | |
\Z(?!\n) # EOL | |
| # --OR-- | |
(?-x:$delimiter) # delimiter | |
| # --OR-- | |
(?!^)(?=["']) # a quote | |
) | |
)//xs or return; # extended layout | |
my ($quote, $quoted, $unquoted, $delim) = (($1 ? ($1,$2) : ($3,$4)), $5, $6); | |
return() unless( defined($quote) || length($unquoted) || length($delim)); | |
if ($keep) { | |
$quoted = "$quote$quoted$quote"; | |
} | |
else { | |
$unquoted =~ s/\\(.)/$1/sg; | |
if (defined $quote) { | |
$quoted =~ s/\\(.)/$1/sg if ($quote eq '"'); | |
$quoted =~ s/\\([\\'])/$1/g if ( $PERL_SINGLE_QUOTE && $quote eq "'"); | |
} | |
} | |
$word .= substr($line, 0, 0); # leave results tainted | |
$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, $word); | |
} | |
} | |
return(@pieces); | |
} | |
sub old_shellwords { | |
# Usage: | |
# use ParseWords; | |
# @words = old_shellwords($line); | |
# or | |
# @words = old_shellwords(@lines); | |
# or | |
# @words = old_shellwords(); # defaults to $_ (and clobbers it) | |
no warnings 'uninitialized'; # we will be testing undef strings | |
local *_ = \join('', @_) if @_; | |
my (@words, $snippet); | |
s/\A\s+//; | |
while ($_ ne '') { | |
my $field = substr($_, 0, 0); # leave results tainted | |
for (;;) { | |
if (s/\A"(([^"\\]|\\.)*)"//s) { | |
($snippet = $1) =~ s#\\(.)#$1#sg; | |
} | |
elsif (/\A"/) { | |
require Carp; | |
Carp::carp("Unmatched double quote: $_"); | |
return(); | |
} | |
elsif (s/\A'(([^'\\]|\\.)*)'//s) { | |
($snippet = $1) =~ s#\\(.)#$1#sg; | |
} | |
elsif (/\A'/) { | |
require Carp; | |
Carp::carp("Unmatched single quote: $_"); | |
return(); | |
} | |
elsif (s/\A\\(.?)//s) { | |
$snippet = $1; | |
} | |
elsif (s/\A([^\s\\'"]+)//) { | |
$snippet = $1; | |
} | |
else { | |
s/\A\s+//; | |
last; | |
} | |
$field .= $snippet; | |
} | |
push(@words, $field); | |
} | |
return @words; | |
} | |
1; | |
__END__ | |
=head1 NAME | |
Text::ParseWords - parse text into an array of tokens or array of arrays | |
=head1 SYNOPSIS | |
use Text::ParseWords; | |
@lists = nested_quotewords($delim, $keep, @lines); | |
@words = quotewords($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_line(), so if you're only splitting | |
one line you can call &parse_line() 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 (including | |
quotes and backslashes) 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 = quotewords('\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 0Z<> | |
a simple word | |
=item 1Z<> | |
multiple spaces are skipped because of our $delim | |
=item 2Z<> | |
use of quotes to include a space in a word | |
=item 3Z<> | |
use of a backslash to include a space in a word | |
=item 4Z<> | |
use of a backslash to remove the special meaning of a double-quote | |
=item 5Z<> | |
another simple word (note the lack of effect of the | |
backslashed double-quote) | |
=back | |
Replacing C<quotewords('\s+', 0, q{this is...})> | |
with C<shellwords(q{this is...})> | |
is a simpler way to accomplish the same thing. | |
=head1 SEE ALSO | |
L<Text::CSV> - for parsing CSV files | |
=head1 AUTHORS | |
Maintainer: Alexandr Ciornii <alexchornyATgmail.com>. | |
Previous maintainer: 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). | |
=head1 COPYRIGHT AND LICENSE | |
This library is free software; you may redistribute and/or modify it | |
under the same terms as Perl itself. | |
=cut | |