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Minimal Types
- Coercion rule
- pi |- 2: real
- pi |- 2+4.5: realexp
- Unicity of typing is lost:
- pi |- 2+3: intexp
- pi |- 2+3: realexp
- Minimal type of every expression:
- pi |- U: theta
- theta <= theta, for all pi |- U:
theta
- Attach each tree node with minimal type!
- Minimal type may not exist:
- nonnegative <= int
- nonpositive <= int
- 0: nonnegative, 0: nonpositive
Wolfgang.Schreiner@risc.uni-linz.ac.at
Id: qualification.tex,v 1.2 1996/05/02 11:53:49 schreine Exp schreine