Clearing String Tag in Logix 5000 Structured Text

Hello all - I have a string tag that is a member of a UDT that I would like to clear within a Structured Text routine - but cannot seem to get it quite right.

The tag that I would like to clear is FTM.TestTag. I have tried to create an empty string tag called FTM.EmptyString, and assign it to FTM.TestTag (to clear it out), but the Structured Text editor does not seem to like the syntax:

FTM.TestTag:=FTM.EmptyString;
FTM.TestTag.LEN:=1;

I get a squiggly syntax error line on the first assignment. I can only seem to make this assignment one element at a time, like:

FTM.TestTag.DATA[0]:=FTM.EmptyString.DATA[0];

...but this only clears the 0th character.

What am I missing here?

Thanks!

COP is available in Structured Text.

COP(empty_string, dest_string, 1) should do it.

COP(FTM.Empty_String, FTM.Test_Tag, 1)

Perfect! Thanks a bunch Bernie!