[pmwiki-devel] adding features to input tags: best practice?

[Dominique Faure]

On 11/14/06, Ben Stallings <Ben at interdependentweb.com> wrote:
> Hello again!  One of the things I need to do in DataQuery is add some
> features to the (:input:) tags... notably, the mask=####-##-## parameter
> so that a JavaScript will help people type dates in the right format,
> because people can be really quirky about how they type dates otherwise,
> and SQL is not at all forgiving.
[...]
> If InputMarkup() were an object method, I could just extend the object.
>   But it's a global function, so that's not an option.  Should I
> redefine the input markup to call a different function?  Or is there a
> better way that would be more compatible with other form recipes?

Few weeks ago, I did some experiments around it, but hadn't enough
time/needs to push them further. Anyway, here's my FormExtensions
recipe skeleton code that you may use as a starting point:

=====8<-----
# Reproduce the core loading order
if (IsEnabled($EnableAuthorTracking, 1))
  include_once("$FarmD/scripts/author.php");
if (IsEnabled($EnablePrefs, 1))
  include_once("$FarmD/scripts/prefs.php");
include_once("$FarmD/scripts/forms.php"); # must come after prefs

# Use our own markup processing
$MarkupTable['input']['rep'] =
  "ExtendedInputMarkup(\$pagename, '$1', PSS('$2'))";

SDVA($ExtendedInputTags, array(
'mytag' => 'InputMyTag',
));

function ExtendedInputMarkup($pagename, $type, $args) {
  global $InputTags, $ExtendedInputTags, $InputAttrs, $InputValues, $FmtV;
  if (@$InputTags[$type]) return InputMarkup($pagename, $type, $args);
  $f = $ExtendedInputTags[$type];
  return isset($f)? $f($pagename, $type, $args) : "(:input $type $args:)";
}

# the (:input mytag ...:) handler itself
function InputMyTag($pagename, $type, $args) {
  $opt = ParseArgs($args);

  return '...';
}
=====8<-----

This code was about to provide handlers for new input types such as:

  (:input mytag ...:)

and gracefully managing predefined ones.

Perhaps, should I make it a recipe by itself, you (and other form
extensions recipes) could bet on?

Regards,
Dom