The %then keyword is used within an if...then...else statement. The %then keyword specifies a set of statements to run if the condition is satisfied.
The optional %else keyword specifies a set of statements to run if the condition is not satisfied.
Syntax
%if <condition> %then <set of statements for when condition is satisfied> [%else <set of statements for when condition is not satisfied>] %endif
In this example the value of the Return Type property is evaluated. If the value of the Return Type property is void, 'return;' is generated, if the value is not void, 'return ReturnValue;' is generated.