conditional if

$if{expr} ... $elif{expr} ... $else ... $fi

The conditional if/elif/else construct, apart from the closing $fi, behaves just like you would expect i.e. as in python, with optional (multiple) $elif{}'s and an optional concluding $else.

The condition expression may be any python expression, that must evaluate without errors in the supplied namespace. As for all directives, being on a single line or spanning many lines has no relevance.