5.2.4.2 value="..." attribute

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5.2.4.2 `value="..."` attribute

Use the `value` attribute to specify a value to be compared with the comparison value of the enclosing `<al-select>` (5.2.3) tag.

    >>> import albatross
    >>> ctx = albatross.SimpleContext('.')
    >>> ctx.locals.opt = 3
    >>> ctx.locals.sel = ['spam', 'eggs']
    >>> albatross.Template(ctx, '<magic>', '''
    ... <al-select name="sel" multiple>
    ...  <al-option value="spam">Spam <al-value expr="opt"> times
    ...  </al-option>
    ...  <al-option>eggs</al-option>
    ...  <al-option>bacon</al-option>
    ... </al-select whitespace>
    ... ''').to_html(ctx)
    >>> ctx.flush_content()
    <select multiple name="sel"><option value="spam" selected>Spam 3 times
     </option><option selected>eggs</option><option>bacon</option></select>