While and do loops #

This page is for designers who meet {while} or {do} in a template. Both repeat while a condition holds. In design templates they are rare: most loops go over a list, which {foreach} does better (Foreach loops).

Contents #

1. while
2. do ... while
3. When to use them

while #

From lib/eztemplate/classes/eztemplatewhilefunction.php:

{while <condition> [sequence <array> as $seqVar]}
    [{delimiter}...{/delimiter}]
    [{break}] [{continue}] [{skip}]
{/while}

{def $level = $node.depth}
{while gt( $level, 1 )}
    <span class="indent"></span>
    {set $level = $level|dec}
{/while}
{undef $level}

The condition is checked before each run; change a variable in the body or the loop never ends.

do ... while #

From lib/eztemplate/classes/eztemplatedofunction.php:

{do}
    ...
{/do while <condition> [sequence <array> as $seqVar]}

The body runs once before the condition is checked.

When to use them #

Almost never in a design. Counting is clearer with {for} (For loops), lists with {foreach}. A runaway loop renders until PHP's time limit; the template engine's template.ini [ControlSettings] MaxLevel limits nesting of templates, not loop runs.

Related pages #

• Foreach loops
• For loops
• Free documentation: this page is free to copy, translate and improve under the GNU FDL 1.3.