Synopsis
<#function name param1 param2 ... paramN>
...
<#return returnValue>
...
</#function>
Where:
-
name: name of method variable (not expression) -
param1,param2, ...etc.: the name of the local variables store the parameter values (not expression), optionally followed by=and the default value (that's an expression). -
paramN, the last parameter, may optionally include a trailing ellipsis (...), which indicates the macro takes a variable number of parameters. Local variableparamNwill be a sequence of the extra parameters. -
returnValue: the expression that calculates the value of the method call.
The return directive can be used anywhere
and for any times between the <#function
...> and
</#function>.
Parameters without default value must precede parameters with
default value
(paramName=defaultValue).
Description
Creates a method variable (in the current namespace, if you
know namespace feature). This directive works in the same way as the
macro
directive, except that return directive
must have a parameter that specifies the return
value of the method, and that attempts to write to the output will
be ignored. If the </#function> is reached
(i.e. there was no return
returnValue), then the return
value of the method is an undefined variable.
Example 1: Creating a method that calculates the average of two numbers:
<#function avg x y>
<#return (x + y) / 2>
</#function>
${avg(10, 20)} will print:
15
Example 2: Creating a method that calculates the average of multiple numbers:
<#function avg nums...>
<#local sum = 0>
<#list nums as num>
<#local sum += num>
</#list>
<#if nums?size != 0>
<#return sum / nums?size>
</#if>
</#function>
${avg(10, 20)}
${avg(10, 20, 30, 40)}
${avg()!"N/A"} will print:
15 25 N/A
