[%# # IMPORTANT NOTE # This documentation is generated automatically from source # templates. Any changes you make here may be lost. # # The 'docsrc' documentation source bundle is available for download # from http://www.template-toolkit.org/docs.html and contains all # the source templates, XML files, scripts, etc., from which the # documentation for the Template Toolkit is built. -%] [% META book = 'Manual' page = 'Filters' %] [% WRAPPER toc; INCLUDE tocitem title='DESCRIPTION'; INCLUDE tocitem title='AUTHOR'; INCLUDE tocitem title='VERSION'; INCLUDE tocitem title='COPYRIGHT'; END %] [% WRAPPER section title='DESCRIPTION' -%]

This section lists all the standard filters distributed with the Template Toolkit for post-processing output.

- format(format)

  The 'format' filter takes a format string as a parameter (as per printf()) and formats each line of text accordingly.

          [% tt_start_tag %] FILTER format('<!-- %-40s -->') [% tt_end_tag %]
          This is a block of text filtered
          through the above format.
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          <!-- This is a block of text filtered        -->
          <!-- through the above format.               -->

- upper

  Folds the input to UPPER CASE.

          [% tt_start_tag %] "hello world" | FILTER upper [% tt_end_tag %]

  output:

          HELLO WORLD

- lower

  Folds the input to lower case.

          [% tt_start_tag %] "Hello World" | FILTER lower [% tt_end_tag %]

  output:

          hello world

- trim

  Trims any leading or trailing whitespace from the input text. Particularly useful in conjunction with INCLUDE, PROCESS, etc., having the same effect as the TRIM configuration option.

          [% tt_start_tag %] INCLUDE myfile | trim [% tt_end_tag %]

- collapse

  Collapse any whitespace sequences in the input text into a single space. Leading and trailing whitespace (which would be reduced to a single space) is removed, as per trim.

          [% tt_start_tag %] FILTER collapse [% tt_end_tag %]

             The   cat

             sat    on

             the   mat

          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          The cat sat on the mat

- html

  Converts the characters '<', '>' and '&' to '&lt;', '&gt;' and '&amp', respectively, protecting them from being interpreted as representing HTML tags or entities.

          [% tt_start_tag %] FILTER html [% tt_end_tag %]
          Binary "<=>" returns -1, 0, or 1 depending on...
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          Binary "&lt;=&gt;" returns -1, 0, or 1 depending on...

- html_para

  This filter formats a block of text into HTML paragraphs. A sequence of two or more newlines is used as the delimiter for paragraphs which are then wrapped in HTML <p>...</p> tags.

          [% tt_start_tag %] FILTER html_para [% tt_end_tag %]
          The cat sat on the mat.

          Mary had a little lamb.
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          <p>
          The cat sat on the mat.
          </p>

          <p>
          Mary had a little lamb.
          </p>

- html_break

  Similar to the html_para filter described above, but uses the HTML tag sequence <br><br> to join paragraphs.

          [% tt_start_tag %] FILTER html_break [% tt_end_tag %]
          The cat sat on the mat.

          Mary had a little lamb.
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          The cat sat on the mat.
          <br>
          <br>
          Mary had a little lamb.

- indent(pad)

  Indents the text block by a fixed pad string or width. The 'pad' argument can be specified as a string, or as a numerical value to indicate a pad width (spaces). Defaults to 4 spaces if unspecified.

          [% tt_start_tag %] FILTER indent('ME> ') [% tt_end_tag %]
          blah blah blah
          cabbages, rhubard, onions
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          ME> blah blah blah
          ME> cabbages, rhubard, onions

- truncate(length)

  Truncates the text block to the length specified, or a default length of 32. Truncated text will be terminated with '...' (i.e. the '...' falls inside the required length, rather than appending to it).

          [% tt_start_tag %] FILTER truncate(21) [% tt_end_tag %]
          I have much to say on this matter that has previously
          been said on more than one occasion.
          [% tt_start_tag %] END [% tt_end_tag %]

  output:

          I have much to say...

- repeat(iterations)

  Repeats the text block for as many iterations as are specified (default: 1).

          [% tt_start_tag %] FILTER repeat(3) [% tt_end_tag %]
          We want more beer and we want more beer,
          [% tt_start_tag %] END [% tt_end_tag %]
          We are the more beer wanters!

  output:

          We want more beer and we want more beer,
          We want more beer and we want more beer,
          We want more beer and we want more beer,
          We are the more beer wanters!

- remove(string)

  Searches the input text for any occurrences of the specified string and removes them. A Perl regular expression may be specified as the search string.

          [% tt_start_tag %] "The  cat  sat  on  the  mat" FILTER remove('\s+') [% tt_end_tag %]

  output:

          Thecatsatonthemat

- replace(search, replace)

  Similar to the remove filter described above, but taking a second parameter which is used as a replacement string for instances of the search string.

          [% tt_start_tag %] "The  cat  sat  on  the  mat" | replace('\s+', '_') [% tt_end_tag %]

  output:

          The_cat_sat_on_the_mat

- redirect(file)

  The 'redirect' filter redirects the output of the block into a separate file, specified relative to the OUTPUT_PATH configuration item.

          [% tt_start_tag %] FOREACH user = myorg.userlist [% tt_end_tag %]
             [% tt_start_tag %] FILTER redirect("users/${user.id}.html") [% tt_end_tag %]
                [% tt_start_tag %] INCLUDE userinfo [% tt_end_tag %]
             [% tt_start_tag %] END [% tt_end_tag %]
          [% tt_start_tag %] END [% tt_end_tag %]

  or more succinctly, using side-effect notation:

          [% tt_start_tag %] INCLUDE userinfo
               FILTER redirect("users/${user.id}.html")
      	   FOREACH user = myorg.userlist
          [% tt_end_tag %]

  A 'file' exception will be thrown if the OUTPUT_PATH option is undefined.

- eval(template_text)

  The 'eval' filter evaluates the block as template text, processing any directives embedded within it. This allows template variables to contain template fragments, or for some method to be provided for returning template fragments from an external source such as a database, which can then be processed in the template as required.

          my $vars  = {
      	fragment => "The cat sat on the [% tt_start_tag %] place [% tt_end_tag %]",
          };
          $template->process($file, $vars);

  The following example:

          [% tt_start_tag %] fragment | eval [% tt_end_tag %]

  is therefore equivalent to

          The cat sat on the [% tt_start_tag %] place [% tt_end_tag %]

  The 'evaltt' filter is provided as an alias for 'eval'.

- perl(perlcode)

  The 'perl' filter evaluates the block as Perl code. The EVAL_PERL option must be set to a true value or a 'perl' exception will be thrown.

          [% tt_start_tag %] my_perl_code | perl [% tt_end_tag %]

  In most cases, the [% tt_start_tag %] PERL [% tt_end_tag %] ... [% tt_start_tag %] END [% tt_end_tag %] block should suffice for evaluating Perl code, given that template directives are processed before being evaluate as Perl. Thus, the previous example could have been written in the more verbose form:

          [% tt_start_tag %] PERL [% tt_end_tag %]
          [% tt_start_tag %] my_perl_code [% tt_end_tag %]
          [% tt_start_tag %] END [% tt_end_tag %]

  as well as

          [% tt_start_tag %] FILTER perl [% tt_end_tag %]
          [% tt_start_tag %] my_perl_code [% tt_end_tag %]
          [% tt_start_tag %] END [% tt_end_tag %]

  The 'evalperl' filter is provided as an alias for 'perl' for backwards compatibility.

- stderr

  The stderr filter prints the output generating by the enclosing block to STDERR

[%- END %] [% WRAPPER section title='AUTHOR' -%]

Andy Wardley <abw@kfs.org>

[% ttlink('http://www.andywardley.com/', 'http://www.andywardley.com/') -%]

[%- END %] [% WRAPPER section title='VERSION' -%]

Template Toolkit version 2.01, released on 30th March 2001.

[%- END %] [% WRAPPER section title='COPYRIGHT' -%]

      Copyright (C) 1996-2001 Andy Wardley.  All Rights Reserved.
      Copyright (C) 1998-2001 Canon Research Centre Europe Ltd.

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

[%- END %]