Re: [Phplib-users] template.inc : Why are blocks parsed over and over again?

[Layne W. <la...@if...>]

> Hi,
>
> because I am trying to understand how exactly template.inc
> works, I put
> some extra debug-stuff in subst():
>
> if ($this->debug & 4) {
>   echo '<b>NOW SHOWING VARKEYS: </b>'.NL;
>   foreach ($this->varkeys as $k => $v) echo "KEY: $k --- VAL: $v ".NL;
>   echo '<b>NOW SHOWING VARVALS: </b>'.NL;
>   foreach ($this->varvals as $k => $v) echo "KEY: $k --- VAL: $v ".NL;
> }
>
>
> (NL is just "<BR>\n")
>
> This showed me, that *each* time I call parse, e.g to parse a block,
> ALL variables are processed everytime. Is this a wanted behaviour?
>
> Could somebody explain this?


It would be non-trivial (and take longer) to discover which variables exist
in a given block. For many pages, this does not cause a performance hit, but
we like to use templates to build selects and lists, so I use 2 instances of
the template class.

For a simple example:

***** sample.html *****
<table>
<tr>
	<th>Name</th>
	<th>Email</th>
</tr>
<!-- BEGIN employee -->
<tr>
	<td>{name}</td>
	<td><a href="mailto:{email}">{email}</a></td>
</tr>
<!-- END employee -->
</table>
***** /sample.html *****


***** sample.php *****

$t = new Template;
$t2 = new Template;

$t->set_file("content", "sample.html");
$t->set_block("content", "employee", "employees");

$t2->set_var("employee", $t->get_var("employee"));

$db = new DB_MySQL;

$db->query("select name, email from employee order by name");
while($db->next_record()) {
	$t2->set_var($db->Record);
	$t2->parse("employees", "employee", true);
}

$t->set_var("employees", $t2->get_var("employees"));

$t->parse("out", "content");
$t->pparse("out");
***** /sample.php *****


This has produced dramatic speed gains on my cluttered pages. Since I do
this many times per page, I clear out all $t2 vars before starting another
loop. I extend Template with the following function to make this easy:

	function clear_vars() {
		$this->varkeys = $this->varvals = array();
	}



Layne Weathers
Ifworld Inc.