When the lookup attribute is specified the result of the expression in the expr (5.4.6.2) attribute is used to retrieve content from the lookup table named in the lookup attribute. This is a very useful way to separate the internal representation of program value from the presentation of that value.
For example:
>>> import albatross >>> ctx = albatross.SimpleContext('.') >>> ctx.locals.simple = 0 >>> ctx.locals.works = 1 >>> albatross.Template(ctx, '<magic>', ''' ... <al-lookup name="bool"><al-item expr="0">FALSE</al-item>TRUE</al-lookup> ... Simple: <al-value expr="simple" lookup="bool" whitespace> ... Works: <al-value expr="works" lookup="bool" whitespace> ... ''').to_html(ctx) >>> ctx.flush_content() Simple: FALSE Works: TRUE
Please refer to the <al-lookup> tag reference for an explanation of that tag and more complex examples.