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 %] |
