Re: [PHP Template] Request for comments - nested sections/looping/padding

Andrei Zmievski wrote:
> 
> I've been thinking a lot about nested sections/looping/repeating values.
> Here's what I came up with.
> 
> * I'm not sure 'repeat' is a good name. I think 'pad' would be better.
> 
> * 'pad' would have one of three values:
>     * 'none'    - means stop looping when the variable with the minimum number
>                   of values is done
>     * 'default' - pad with the default value, or empty string if default is
>                   not specified
>     * 'last'    - pad with the last value of the variable (or the only value
>                   if it's not an array)
> 
>     By default, I think, 'pad' should be 'default' for arrays, and 'last'
>     for variables with single value. Some examples:
> 
>     1. Let's say we have $color = array("red", "green", "blue"), and $size =
>     array("large", "small"). If we have this template piece:
> 
>     {{section}}
>         {{ $color }} - {{ $size }}
>     {{/section}}
> 
>     Then by default it will output:
> 
>         red   - large
>         green - small
>         blue  -
> 
>     If we use {{ $size default="none" }}, then we'd have:
> 
>         red   - large
>         green - small
>         blue  - none
> 
>     If we use {{ $size pad=none }}, we'd have:
> 
>         red   - large
>         green - small
> 
>     2. Let's say we have $domain = "php.net", $name = array("joe",
>     "andrei").
> 
>     {{section}}
>         {{ $name }}@{{ $domain }}
>     {{/section}}
> 
>     Then by default it will output:
> 
>         [email protected]
>         [email protected]
> 
>     If we use {{ $size pad=last }}, we'd have:
> 
>         [email protected]
>         andrei@
> 
> * Imagine this scenario:
> 
>     {{section category}}
>         Category: {{ $catname }}
>         {{section article}}
>             {{ $headline }} - {{ $date }}
>         {{/section article}}
>     {{/section category}}
> 
>     What we want to do here is display a list of categories, and for each
>     category, display the list of headlines and dates in it. So, we'll have
>     to assign the data like this:
> 
>     tmpl_assign($id, "catname", array("Sports", "News"));
>     tmpl_assign($id, "headline", array("Sports Headline 1"),
>                                  array("News Headline 1", "News Headline 2"));
>     tmpl_assign($id, "date", array("02/20/00", array("02/21/00", "02/23/00"));
> 
>     Or if you are receiving data incrementally, you'd use tmpl_add_value(),
>     assuming $sql->record["headline"] contains all the headlines for a
>     category, and so on:
> 
>     while ($sql->next()) {
>         tmpl_add_value($id, "catname", $sql->record["Category"]);
>         tmpl_add_value($id, "headline", $sql->record["headline"]);
>         tmpl_add_value($id, "date", $sql->record["date"]);
>     }
> 
>     Is this clear?
> 
>     Basically, after the section loops through one set of values, it
>     increments internal pointer so that the next time 'article' section is
>     entered into, it will loop through the next set of values.
> 
> * You can refer to the current value of variable as it exists in another
>   section using $<section name>/<var name>, e.g. $category/catname
> 
> * The variables in outer sections are visible to inner ones, e.g.
>   $category/catname, but outer sections cannot look inside inner ones, e.g.
>   $article/headline will give you nothing when used outside the 'article'
>   section. But it might be useful to do #article/TOTAL to get the total
>   number of headlines/dates that were printed. We'll have to think more
>   about what happens when you refer to $article/headline from outside.
> 
> * Imagine that we want to print the categories and articles like this:
> 
>     News        News Headline 1     02/21/00
>                 News Headline 2     02/23/00
>     Sports      Sports Headline 1   02/20/00
> 
>   Now, how would you do this? Each row would have to be printed in the
>   'article' section, but we need to loop through $catname too, getting each
>   next value only when the 'article' section looping is done. I think we can
>   do it like this:
> 
>     {{section category}}
>         {{section article}}
>         Category: {{ $category/catname pad=default }} {{ $headline }} {{ $date }}
>         {{/section article}}
>     {{/section category}}
> 
>   So, even though $catname is not seen in 'category' section, it is assigned
>   to it by virtue of having been mentioned as $category/catname. Thus on the
>   first iteration of the 'article' loop, we'll print:
> 
>     News        News Headline 1     02/21/00
> 
>   Then, since pad=default and $category/catname has only a single value,
>   we're going to output default (which is empty here) and we'd have:
> 
>                 News Headline 2     02/23/00
> 
>   Now, 'article' looping is done and it will increment internal pointer to
>   go to the next set of values. 'category' looping is also done, so it's
>   going to go to 'Sports' now, and the next printed thing will be:
> 
>     Sports      Sports Headline 1   02/20/00
> 
>   And we have our desired result.
> 
> I think the basic ideas are good and pretty flexible, we might want to come
> up with really good names for attributes and values so that the designer is
> not too confused.  I'm not sure about 'pad', 'default', 'last', etc.
> 
> -Andrei
> 

Something to consider, it might be confusing to have attributes and
values the same name,
for example:

{{ section default="none" pad="default" }}