5.2.2.9 prevpage="..." and nextpage="..." attributes

The prevpage and nextpage attributes respectively select the previous and next pages of an <al-for> ListIterator (5.4.8.9).

An attribute value must be supplied that specifies the name of the iterator.

The name (5.2.2.5) attribute is generated as follows:

>>> import albatross
>>> ctx = albatross.SimpleContext('.')
>>> albatross.Template(ctx, '<magic>', '''
... <al-input type="image" nextpage="i" srcicons/right.gif" border="0" whitespace>
... ''').to_html(ctx)
>>> ctx.flush_content()
<input type="image" srcicons/right.gif" border="0" name="nextpage,i" />

When merging the browser request the NamespaceMixin.set_value() (7.6) method looks for field names that contain commas. These names are split into operation, iterator, and optional value then the set_backdoor() method of the identified iterator is invoked.

During request merging the above example will execute code equivalent to the following.

ctx.locals.i.set_backdoor('nextpage', 'nextpage,i')