Passing ByRef at second call level

charvista · **Posted:** Sun Mar 18, 2012 11:25 am

Hello all
I have a problem here. I am not sure how to pass the variable *v\s to a second call. I know that when I need to pass a variable, I should use @v.....
What should I change in the program so the final result is tvar\s="change #1 and change #2" ?

Code:

; This is how to use ByRef with string variables, which are in fact pointers

Procedure change2(*v.string)
    *v\s+" and change #2"
    Debug *v\s
EndProcedure

Procedure change1(*v.string)
    *v\s="change #1"
    Debug *v\s
    change2(@v); this is my problem <<<<<<<<<<
EndProcedure



Define.string tvar ; or Define tvar.string
tvar\s="initial-value"
Debug "before call: "+tvar\s
Debug "================================"
change1(@tvar)
Debug "================================"
Debug "after call: "+tvar\s

Thanks in advance!

wilbert · **Posted:** Sun Mar 18, 2012 11:35 am

Pass the pointer

Code:

; This is how to use ByRef with string variables, which are in fact pointers

Procedure change2(*v.string)
    *v\s+" and change #2"
    Debug *v\s
EndProcedure

Procedure change1(*v.string)
    *v\s="change #1"
    Debug *v\s
    change2(*v)
EndProcedure



Define.string tvar ; or Define tvar.string
tvar\s="initial-value"
Debug "before call: "+tvar\s
Debug "================================"
change1(@tvar)
Debug "================================"
Debug "after call: "+tvar\s

charvista · **Posted:** Sun Mar 18, 2012 12:20 pm

Thank you Wilbert.
It was too simple... we all have (many?) holes in the head, and the needed info is exactly there :mrgreen:

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Passing ByRef at second call level

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