phpman > perldoc > Text::Trim

NAME
    Text::Trim - remove leading and/or trailing whitespace from strings

VERSION
    version 1.04

SYNOPSIS
        use Text::Trim;

        $text = "\timportant data\n";
        $data = trim $text;
        # now $data contains "important data" and $text is unchanged

        # or:
        trim $text; # work in-place, $text now contains "important data"

        @lines = <STDIN>;
        rtrim @lines; # remove trailing whitespace from all lines

        # Alternatively:
        @lines = rtrim <STDIN>;

        # Or even:
        while (<STDIN>) {
            trim; # Change $_ in place
            # ...
        }

DESCRIPTION
    This module provides functions for removing leading and/or trailing whitespace from strings. It
    is basically a wrapper around some simple regexes with a flexible context-based interface.

EXPORTS
    All functions are exported by default.

CONTEXT HANDLING
  void context
    Functions called in void context change their arguments in-place

        trim(@strings); # All strings in @strings are trimmed in-place

        ltrim($text);   # remove leading whitespace on $text

        rtrim;          # remove trailing whitespace on $_

    No changes are made to arguments in non-void contexts.

  list context
    Values passed in are changed and returned without affecting the originals.

        @result = trim(@strings);    # @strings is unchanged

        @result = rtrim;             # @result contains rtrimmed $_

        ($result) = ltrim(@strings); # like $result = ltrim($strings[0]);

  scalar context
    As list context but multiple arguments are stringified before being returned. Single arguments
    are unaffected. This means that under these circumstances, the value of $" ($LIST_SEPARATOR) is
    used to join the values. If you don't want this, make sure you only use single arguments when
    calling in scalar context.

        @strings = ("\thello\n", "\tthere\n");
        $trimmed = trim(@strings);
        # $trimmed = "hello there"

        local $" = ', ';
        $trimmed = trim(@strings);
        # Now $trimmed = "hello, there"

        $trimmed = rtrim;
        # $trimmed = $_ minus trailing whitespace

  Undefined values
    If any of the functions are called with undefined values, the behaviour is in general to pass
    them through unchanged. When stringifying a list (calling in scalar context with multiple
    arguments) undefined elements are excluded, but if all elements are undefined then the return
    value is also undefined.

        $foo = trim(undef);        # $foo is undefined
        $foo = trim(undef, undef); # $foo is undefined
        @foo = trim(undef, undef); # @foo contains 2 undefined values
        trim(@foo)                 # @foo still contains 2 undefined values
        $foo = trim('', undef);    # $foo is ''

FUNCTIONS
  trim
    Removes leading and trailing whitespace from all arguments, or $_ if none are provided.

  rtrim
    Like "trim()" but removes only trailing (right) whitespace.

  ltrim
    Like "trim()" but removes only leading (left) whitespace.

UNICODE
    Because this module is implemented using Perl regular expressions, it is capable of recognising
    and removing unicode whitespace characters (such as non-breaking spaces) from scalars with the
    utf8 flag on. See Encode for details about the utf8 flag.

    Note that this only applies in the case of perl versions after 5.8.0 or so.

SEE ALSO
    Brent B. Powers' String::Strip performs a similar function in XS.

AUTHORS
    Matt Lawrence <mattlaw AT cpan.org> - Original author and maintainer

    Ryan Thompson <rjt AT cpan.org> - Co-maintainer, miscellaneous fixes

SUPPORT
    <https://github.com/rjt-pl/Text-Trim/issues>: Bug reports and feature requests

    <https://github.com/rjt-pl/Text-Trim.git>: Source repository

ACKNOWLEDGEMENTS
    Terrence Brannon <metaperl AT gmail.com> for bringing my attention to String::Strip and suggesting
    documentation changes.

LICENSE
    This program is free software; you can redistribute it and/or modify it under the same terms as
    Perl itself.

    <http://dev.perl.org/licenses/artistic.html>