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Semantics
- General typing patterns:
-
p |- U:H |
define I=U:
{I:H}dec
|
- p |-invoke I: H, if (I:H) in p
- Procedures: lazy evaluation.
- [[p |- proc I=C: {I:comm}dec]]e s
= {I=r},
where r(s') = [[p |- C: comm]]e s'.
- [[p |- call I: comm]]e s = r(s)
where (I=r) in e.
- Eager procedures: backtracking (non-local jumps).
- [[p |- proc I=C: {I:comm}dec]]e s
= {I=s'},
where s' = [[p |- C: comm]]e s.
- [[p |- call I: comm]]e s = s', where
(I=s') in e.
- Constants: eager evaluation.
- [[p |- const I=N: {I:int}dec]]e s
= {I=n},
where n = [[p |- N: int]]e.
Wolfgang.Schreiner@risc.uni-linz.ac.at
Id: abstraction.tex,v 1.1 1996/03/05 08:55:21 schreine Exp schreine