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Semantics of Dynamic Scoping
- Phrase's environment not determined until phrase is evaluated!
-
[[define I=U]] = ({I=}, )
where = [[U]]
-
[[invoke I]] =
where (I=) in
- Environment behaves like store!
- Semantics for untyped phrases
- Types of phrases cannt be predicated.
- Well-formedness of semantics in question.
- Strange programs can be written:
- begin proc P = call P in call
P end
- [[...]] = ( -U- {=})
- must receive itself as argument!
Wolfgang.Schreiner@risc.uni-linz.ac.at
Id: qualification.tex,v 1.2 1996/05/02 11:53:49 schreine Exp schreine