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.
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:
0 a simple word
1 multiple spaces are skipped because of our $delim
2 use of quotes to include a space in a word
3 use of a backslash to include a space in a word
quote
4 use of a backslash to remove the special meaning of a double-
double-quote)
5 another simple word (note the lack of effect of the backslashed
Replacing "ewords('\s+', 0, q{this is...}) with
&shellwords(q{this is...}) is a simpler way to accomplish
the same thing.
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).