I would say that display logic is a FILTER of what the business logic returns.
Well, it's not what you can _say_, it's what you can _substantiate_ :) Take a look at this tt: 

<h3>Projects</h3>
<ul>
[% FOREACH project IN worklist(me.id) %]
   <li> <a href="[% project.url %]">[% project.name %]</a>
[% END %]
</ul>

[download]
It is pseudo-English for the business requirement: "For each project in the worklist provide a URL linking to the project name"

That is a business rule, plain and simple, and it has crept it's way out of Perl and into a quote-unquote presentation language.

In reply to tt splits your business logic between Perl and its 'presentation language' by metaperl
in thread Display logic is driven by business rules IMHO by metaperl

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.