htp on-line reference : IF, ELSEIF, ELSE, /IF

syntax

<IF [NOT] conditional>
    block #1
[
<ELSEIF [NOT] conditional>
    block #2
...
]
[
<ELSE>
    block #3
]
</IF>



synopsis

"Conditional" is either a "compare" or "is defined" operation. A compare operator is a test of the value of a macro against a literal string:

    <IF name="Jim">...</IF>


and a defined operator is a test of a macro's existance:

    <IF name>...</IF>


If the NOT tag is present in the IF markup, the evaluation of the conditional is reversed. The first IF or ELSEIF condition that evaluates to true is chosen. If none of the conditions is true the ELSE block is taken if it is present. A conditional block must be closed with the /IF tag. IF tags can be nested.