Template::Plugin::Table - Plugin to present data in a table


Template::Plugin::Table - Plugin to present data in a table


    [% USE table(list, rows=n, cols=n, overlap=n, pad=0) %]
    [% FOREACH item = table.row(n) %]
       [% item %]
    [% END %]
    [% FOREACH item = table.col(n) %]
       [% item %]
    [% END %]
    [% FOREACH row = table.rows %]
       [% FOREACH item = row %]
          [% item %]
       [% END %]
    [% END %]
    [% FOREACH col = table.cols %]
       [% col.first %] - [% col.last %] ([% col.size %] entries)
    [% END %]


The Table plugin allows you to format a list of data items into a virtual table. When you create a Table plugin via the USE directive, simply pass a list reference as the first parameter and then specify a fixed number of rows or columns.

    [% USE Table(list, rows=5) %]
    [% USE table(list, cols=5) %]

The 'Table' plugin name can also be specified in lower case as shown in the second example above. You can also specify an alternative variable name for the plugin as per regular Template Toolkit syntax.

    [% USE mydata = table(list, rows=5) %]

The plugin then presents a table based view on the data set. The data isn't actually reorganised in any way but is available via the row(), col(), rows() and cols() as if formatted into a simple two dimensional table of n rows x n columns. Thus, if our sample 'alphabet' list contained the letters 'a' to 'z', the above USE directives would create plugins that represented the following views of the alphabet.

    [% USE table(alphabet, ... %]
    rows=5                  cols=5
    a  f  k  p  u  z        a  g  m  s  y
    b  g  l  q  v           b  h  n  t  z
    c  h  m  r  w           c  i  o  u
    d  i  n  s  x           d  j  p  v
    e  j  o  t  y           e  k  q  w
                            f  l  r  x

We can request a particular row or column using the row() and col() methods.

    [% USE table(alphabet, rows=5) %]
    [% FOREACH item = table.row(0) %]
       # [% item %] set to each of [ a f k p u z ] in turn
    [% END %]
    [% FOREACH item = table.col(2) %]
       # [% item %] set to each of [ m n o p q r ] in turn
    [% END %]

Data in rows is returned from left to right, columns from top to bottom. The first row/column is 0. By default, rows or columns that contain empty values will be padded with the undefined value to fill it to the same size as all other rows or columns. For example, the last row (row 4) in the first example would contain the values [ e j o t y undef ]. The Template Toolkit will safely accept these undefined values and print a empty string. You can also use the IF directive to test if the value is set.

   [% FOREACH item = table.row(4) %]
      [% IF item %]
         Item: [% item %]
      [% END %]
   [% END %]

You can explicitly disable the 'pad' option when creating the plugin to returned shortened rows/columns where the data is empty.

   [% USE table(alphabet, cols=5, pad=0) %]
   [% FOREACH item = table.col(4) %]
      # [% item %] set to each of 'y z'
   [% END %]

The rows() method returns all rows/columns in the table as a reference to a list of rows (themselves list references). The row() methods when called without any arguments calls rows() to return all rows in the table.

Ditto for cols() and col().

    [% USE table(alphabet, cols=5) %]
    [% FOREACH row = table.rows %]
       [% FOREACH item = row %]
          [% item %]
       [% END %]
    [% END %]

The Template Toolkit provides the first(), last() and size() methods that can be called on list references to return the first/last entry or the number of entried. The following example shows how we might use this to provide an alphabetical index split into 3 even parts.

    [% USE table(alphabet, cols=3, pad=0) %]
    [% FOREACH group = table.col %]
       [ [% group.first %] - [% group.last %] ([% group.size %] letters) ]
    [% END %]

This produces the following output:

    [ a - i (9 letters) ]
    [ j - r (9 letters) ]
    [ s - z (8 letters) ]

We can also use the general purpose join() list method which joins the items of the list using the connecting string specified.

    [% USE table(alphabet, cols=5) %]
    [% FOREACH row = table.rows %]
       [% row.join(' - ') %]
    [% END %]

Data in the table is ordered downwards rather than across but can easily be transformed on output. For example, to format our data in 5 columns with data ordered across rather than down, we specify 'rows=5' to order the data as such:

    a  f  .  .
    b  g  .
    c  h
    d  i
    e  j

and then iterate down through each column (a-e, f-j, etc.) printing the data across.

    a  b  c  d  e
    f  g  h  i  j
    .  .

Example code to do so would be much like the following:

    [% USE table(alphabet, rows=3) %]
    [% FOREACH cols = table.cols %]
      [% FOREACH item = cols %]
        [% item %]
      [% END %]
    [% END %]
    a  b  c
    d  e  f
    g  h  i
    j  .  .

In addition to a list reference, the Table plugin constructor may be passed a reference to a Template::Iterator object or subclass thereof. The get_all() method is first called on the iterator to return all remaining items. These are then available via the usual Table interface.

    [% USE DBI(dsn,user,pass) -%]
    # query() returns an iterator
    [% results = DBI.query('SELECT * FROM alphabet ORDER BY letter') %]

    # pass into Table plugin
    [% USE table(results, rows=8 overlap=1 pad=0) -%]
    [% FOREACH row = table.cols -%]
       [% row.first.letter %] - [% row.last.letter %]:
          [% row.join(', ') %]
    [% END %]


Andy Wardley <abw@andywardley.com>



2.59, distributed as part of the Template Toolkit version 2.10, released on 24 July 2003.


  Copyright (C) 1996-2003 Andy Wardley.  All Rights Reserved.
  Copyright (C) 1998-2002 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.



 Template::Plugin::Table - Plugin to present data in a table