Module DT_If

source code

Conditional insertion

Conditional insertion is performed using 'if' and 'else'
commands.

To include text when an object is true using the EPFS
format, use::

   %(if name)[
        text
   %(if name)]

To include text when an object is true using the HTML
format, use::

   <!--#if name-->
        text
   <!--#/if name-->

where 'name' is the name bound to the object.

To include text when an object is false using the EPFS
format, use::

   %(else name)[
        text
   %(else name)]

To include text when an object is false using the HTML
format, use::

   <!--#else name-->
        text
   <!--#/else name-->

Finally to include text when an object is true and to
include different text when the object is false using the
EPFS format, use::

   %(if name)[
        true text
   %(if name)]
   %(else name)[
        false text
   %(else name)]

and to include text when an object is true and to
include different text when the object is false using the
HTML format, use::

   <!--#if name-->
        true text
   <!--#else name-->
        false text
   <!--#/if name-->

Notes:

- if a variable is nor defined, it is considered to be false.

- A variable if only evaluated once in an 'if' tag.  If the value
  is used inside the tag, including in enclosed tags, the
  variable is not reevaluated.