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Consequences of Correspondence
- Semantics of identifiers:
- Independent of way in which identifier is bound.
- Understanding more easy.
- Direction for language extension:
- Existing abstraction (e.g. procedures).
- Introduce parameter form (e.g. command parameter).
- Correspondence may fail:
- Evaluate functions lazily but expression parameters eagerly.
- var A: newint; fun F = @A+1
proc P(X: intexp) = A:=X+F;
A:=X+F
- Both X and F have type intexp.
- X and F are evaluated differently.
- Syntactic distinction: A:=X+(eval F)
Wolfgang.Schreiner@risc.uni-linz.ac.at
Id: parameter.tex,v 1.1 1996/04/25 11:40:48 schreine Exp schreine