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FPC and bitwise negation

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Mike James:
I'm interested in language design and I'm writing a compiler for a Oberon-like language using Coco-R. The bitwise negation is define as :


--- Code: ---Factor =  /* others */ | "NOT" Factor.
--- End code ---

This means that the following code fragment is legit:


--- Code: ---mybool := NOT NOT NOT NOT mybool;
--- End code ---

I checked the same code fragment under FreePascal and this allows it also.

It got me thinking: Should it be flagged as a warning (or even a mild rebuke  :D) and when would it ever be useful to allow such a construction?

-=mike=-

marcov:
Repeated unary NOTs are fairly easily optimizable, and logically sound (though redundant) so why would one unnecesarily burden the compiler (and increase warning/hint noise)?

Both the compiler developer and user have better things to do.

Only exception I can imagine is compilers and, more importantly, source analysers for training/educational purposes. 

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