NAME

       xmlif - conditional processing instructions for XML

SYNOPSIS

       xmlif [attrib=value...]

DESCRIPTION

       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 color='white'.

       Here is an example:

           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.
           <?xmlif else?>
           Otherwise issue this text.
           <?xmlif fi?>
           Always issue this text.

AUTHOR

       Eric S. Raymond <esr@snark.thyrsus.com>
           Author of xmlif program