xmlif - conditional processing instructions for XML
xmlif filters XML according to conditionalizing markup. This can be useful for
formatting one of several versions of an XML document depending on conditions
passed to the command.
Attribute/value pairs from the command line are matched against the attributes
associated with certain processing instructions in the document. The
instructions are <?xmlif if?> and its inverse <?xmlif if not?>,
<?xmlif elif?> and its inverse <?xmlif elif not?>, <?xmlif
else?>, and <?xmlif fi?>.
Argument/value pairs given on the command line are checked against the value of
corresponding attributes in the conditional processing instructions. An
`attribute match' happens if an attribute occurs in both the command-line
arguments and the tag, and the values match. An `attribute mismatch' happens
if an attribute occurs in both the command-line arguments and the tag, but the
values do not match.
Spans between <?xmlif if?> or <?xmlif elif?> and the next
conditional processing instruction at the same nesting level are passed
through unaltered if there is at least one attribute match and no attribute
mismatch; spans between <?xmlif if not?> and <?xmlif elif not?>
and the next conditional processing instruction are passed otherwise. Spans
between <?xmlif else?> and the next conditional-processing tag are
passed through only if no previous span at the same level has been passed
through. <?xmlif if?> and <?xmlif fi?> (and their `not' variants)
change the current nesting level; <?xmlif else?> and <?xmlif
elif?> do not.
All these processing instructions will be removed from the output produced.
Aside from the conditionalization, all other input is passed through
untouched; in particular, entity references are not resolved.
Value matching is by string equality, except that "|" in an attribute
value is interpreted as an alternation character. Thus, saying foo='red|blue'
on the command line enables conditions red and blue. Saying
color='black|white' in a tag matches command-line conditions color='black' and
Here is an example:
Eric S. Raymond
Always issue this text.
<?xmlif if condition='html'?>
Issue this text if 'condition=html' is given on the command line.
<?xmlif elif condition='pdf|ps'?>
Issue this text if 'condition=pdf' or 'condition=ps'
is given on the command line.
Otherwise issue this text.
Always issue this text.
Author of xmlif program