Funny - was wondering the same thing a little while back for a development tool helper.
I don't think there is a to detect this however.
What do you need this for? Maybe there's another way to do what you need without specifically checking for a ref/value parm.
+++ Rick ---
>Does anyone know of a way to determine if a variable has been passed to a function by reference or by value. This is a run-time question.
>For example:
>
>local a
>a='test'
>=Test(@a)
>=Test(a)
>
>procedure Text
>lparameter b
>*-- here, i would like to verify that the variable 'a' was passed to 'b' as by reference.
>...
>