Re^3: When to use templates?

[cfreak]

in reply to Re^2: When to use templates?
in thread When to use templates?

*Purest Alert*

Why do you need complex IF statements in your template? samtregar's idea for HTML::Template was to separate the two. If you introduce complexity into your template you create a Meta-language where code and data are again mixed. And designers get confused :)

I believe its much better to leave complex stuff in Perl which is very good at handling it and output the appropriate data to the template from there.

I do make use of HTML::Template's simple IF statements (and I wish there was an elseif) but beyond them I don't think its appropriate to further extend a meta-language.

[zejames]

I said complex statement, meaning statement not only based on boolean variable passed par the perl script.

In HTML::Template for example, you cannot test in the template if $var > 5, you have to do it the script ($bool = $var > 5;) and then use the result the a TMPL_IF.

I do not like it very much. However, I do respect Your Way To Code It ;) That's a matter of choice.

[MidLifeXis]

I agree mostly with that sentiment. However, I have found myself putting display oriented variables in my perl code lately.

For example, with HT, I would need to do a ...

# In the perl
$template->param(SHOULD_I_DISPLAY_THIS => ($foo + $bar) > 2);
-------
<!-- In the template -->
<TMPL_IF SHOULD_I_DISPLAY_THIS>this</TMPL_IF>

With HTE, I could use...

<TMPL_IF EXPR="(FOO + BAR) > 2">this</TMPL_IF>

It leaves the display decisions in the hands of the interface / html coder, and the data collection to the perl program. It is hard (you mentioned not having a TMPL_ELSIF) to do an N (where N>2) way decision, or a decision based on the quantity of something.

Another example...

Without creating display variables in your perl code (x_gt_3, x_gt_5, ...), how would you change the style of something based on its value?

• Green if X < 3
• orange if 3 <= X < 5
• red if 5 <= X

As I said above, I typically don't like using HTE, but I am running into more instances where it could prove to be useful, and would remove some of the variables controling display from my perl code.