5.3.8.4 flow="..." attribute

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5.3.8.4 `flow="..."` attribute

This attribute is used with the `cols` (5.3.8.1) attribute to control the flow of values across columns. The default value is `"down"`. Use the value `"across"` to flow items across columns.

Rather than evaluate the enclosed content once for each item in the sequence, the tag evaluates the content for each row of items in the sequence. The items in each row can be formatted by using an inner `<al-for>` tag.

For example:

    >>> import albatross
    >>> ctx = albatross.SimpleContext('.')
    >>> albatross.Template(ctx, '<magic>', '''
    ... <al-for iter="i" expr="range(15)" cols="4" flow="across">
    ...  <al-for iter="c" expr="i.value()">
    ...   <al-value expr="' %2d' % c.value()">
    ...  </al-for whitespace>
    ... </al-for>
    ... ''').to_html(ctx)
    >>> ctx.flush_content()
      0  1  2  3
      4  5  6  7
      8  9 10 11
     12 13 14

Multi-column formatting does not support pagination.