Programming Language Theory: Difference between revisions
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*** ''Invariant'' modifications dissolve the subsumption relation | *** ''Invariant'' modifications dissolve the subsumption relation | ||
* Support for ''minimal'' and ''maximal'' types (also known as Bottom and Top) | * Support for ''minimal'' and ''maximal'' types (also known as Bottom and Top) | ||
** Bottom (no values) + Top (all values) + subtyping ⇒ ''bounded type lattice'' | |||
===Conversion=== | ===Conversion=== | ||
Treatment of a value of a given type as if it had another type, possibly involving modification of the underlying representation, or storage/alignment requirements thereof. When done explicitly, conversion is referred to as ''casting''; when done implicitly, it is called ''coercion''. | Treatment of a value of a given type as if it had another type, possibly involving modification of the underlying representation, or storage/alignment requirements thereof. When done explicitly, conversion is referred to as ''casting''; when done implicitly, it is called ''coercion''. | ||