Text::Wrap(3p) Perl Programmers Reference Guide Text::Wrap(3p) #
Text::Wrap(3p) Perl Programmers Reference Guide Text::Wrap(3p)
NNAAMMEE #
Text::Wrap - line wrapping to form simple paragraphs
SSYYNNOOPPSSIISS #
EExxaammppllee 11
use Text::Wrap;
$initial_tab = "\t"; # Tab before first line
$subsequent_tab = ""; # All other lines flush left
print wrap($initial_tab, $subsequent_tab, @text);
print fill($initial_tab, $subsequent_tab, @text);
$lines = wrap($initial_tab, $subsequent_tab, @text);
@paragraphs = fill($initial_tab, $subsequent_tab, @text);
EExxaammppllee 22
use Text::Wrap qw(wrap $columns $huge);
$columns = 132; # Wrap at 132 characters
$huge = 'die';
$huge = 'wrap';
$huge = 'overflow';
EExxaammppllee 33
use Text::Wrap;
$Text::Wrap::columns = 72;
print wrap('', '', @text);
DDEESSCCRRIIPPTTIIOONN #
"Text::Wrap::wrap()" is a very simple paragraph formatter. It formats a
single paragraph at a time by breaking lines at word boundaries.
Indentation is controlled for the first line ($initial_tab) and all
subsequent lines ($subsequent_tab) independently. Please note:
$initial_tab and $subsequent_tab are the literal strings that will be
used: it is unlikely you would want to pass in a number.
"Text::Wrap::fill()" is a simple multi-paragraph formatter. It formats
each paragraph separately and then joins them together when it's done.
It will destroy any whitespace in the original text. It breaks text into
paragraphs by looking for whitespace after a newline. In other respects,
it acts like wwrraapp(()).
"wrap()" compresses trailing whitespace into one newline, and "fill()"
deletes all trailing whitespace.
Both "wrap()" and "fill()" return a single string.
Unlike the old Unix ffmmtt(1) utility, this module correctly accounts for
any Unicode combining characters (such as diacriticals) that may occur in
each line for both expansion and unexpansion. These are overstrike
characters that do not increment the logical position. Make sure you
have the appropriate Unicode settings enabled.
OOVVEERRRRIIDDEESS #
"Text::Wrap::wrap()" has a number of variables that control its behavior.
Because other modules might be using "Text::Wrap::wrap()" it is suggested
that you leave these variables alone! If you can't do that, then use
"local($Text::Wrap::VARIABLE) = YOURVALUE" when you change the values so
that the original value is restored. This "local()" trick will not work
if you import the variable into your own namespace.
Lines are wrapped at $Text::Wrap::columns columns (default value: 76).
$Text::Wrap::columns should be set to the full width of your output
device. In fact, every resulting line will have length of no more than
"$columns - 1".
It is possible to control which characters terminate words by modifying
$Text::Wrap::break. Set this to a string such as '[\s:]' (to break before
spaces or colons) or a pre-compiled regexp such as "qr/[\s']/" (to break
before spaces or apostrophes). The default is simply '\s'; that is, words
are terminated by spaces. (This means, among other things, that trailing
punctuation such as full stops or commas stay with the word they are
"attached" to.) Setting $Text::Wrap::break to a regular expression that
doesn't eat any characters (perhaps just a forward look-ahead assertion)
will cause warnings.
Beginner note: In example 2, above $columns is imported into the local
namespace, and set locally. In example 3, $Text::Wrap::columns is set in
its own namespace without importing it.
"Text::Wrap::wrap()" starts its work by expanding all the tabs in its
input into spaces. The last thing it does it to turn spaces back into
tabs. If you do not want tabs in your results, set $Text::Wrap::unexpand
to a false value. Likewise if you do not want to use 8-character
tabstops, set $Text::Wrap::tabstop to the number of characters you do
want for your tabstops.
If you want to separate your lines with something other than "\n" then
set $Text::Wrap::separator to your preference. This replaces all
newlines with $Text::Wrap::separator. If you just want to preserve
existing newlines but add new breaks with something else, set
$Text::Wrap::separator2 instead.
When words that are longer than $columns are encountered, they are broken
up. "wrap()" adds a "\n" at column $columns. This behavior can be
overridden by setting $huge to 'die' or to 'overflow'. When set to
'die', large words will cause "die()" to be called. When set to
'overflow', large words will be left intact.
Historical notes: 'die' used to be the default value of $huge. Now,
'wrap' is the default value.
EEXXAAMMPPLLEESS #
Code:
print wrap("\t","",<<END);
This is a bit of text that forms
a normal book-style indented paragraph
END #
Result:
" This is a bit of text that forms
a normal book-style indented paragraph
"
Code:
$Text::Wrap::columns=20;
$Text::Wrap::separator="|";
print wrap("","","This is a bit of text that forms a normal book-style paragraph");
Result:
"This is a bit of|text that forms a|normal book-style|paragraph"
SSEEEE AALLSSOO #
For correct handling of East Asian half- and full-width characters, see
Text::WrapI18N. For more detailed controls: Text::Format.
AAUUTTHHOORR #
David Muir Sharnoff <cpan@dave.sharnoff.org> with help from Tim Pierce
and many many others.
LLIICCEENNSSEE #
Copyright (C) 1996-2009 David Muir Sharnoff. Copyright (C) 2012-2013
Google, Inc. This module may be modified, used, copied, and
redistributed at your own risk. Although allowed by the preceding
license, please do not publicly redistribute modified versions of this
code with the name "Text::Wrap" unless it passes the unmodified
Text::Wrap test suite.
perl v5.36.3 2023-02-15 Text::Wrap(3p)