Generic functions provide a form of polymorphism allowing many
implementation methods with varying parameter types, called
specializers. Methods on a given generic function are chosen
according to applicability and are then ordered by specificity.
A method is applicable if each argument is an instance of each
corresponding specializer.
A method A is more specific than method B
if all of A's specializers are subtypes of B's.
During method dispatch three cases can occur:
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<gen> | (<fun>) | C |
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fun-mets | (x|<gen> => <lst>) | P |
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| returns x's methods. | |
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gen-add-met | (x|<gen> y|<met> => <gen>) | G |
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| adds method y to generic x. | |
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ord-app-mets | (x|<gen> args|... => (tup ord|<lst> amb|<lst>)) | G |
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| returns both the list of sorted applicable methods and any ambiguous
methods when generic x is called with arguments args. | |
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DG | (DG ,name ,sig) | S |
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| defines a binding with name ,name bound to a generic with signature ,sig. | |
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