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Module Generic.Consumer

module Consumer: Generic_core_consumer
Extensible type-indexed consumers.
type 'b ty_fun = {
   f : 'a. 'a Ty.ty -> 'a -> 'b;
}
Type-indexed consumer function
type 'b closure = {
   f : 'a. 'a Ty.ty -> 'a -> 'b; (*
f: applies the extensible function.
Raises Generic_core_extensible.Type_pattern_match_failure when the type index doesn't match any of the patterns in the collection.
*)
   ext : 'a. 'a Ty.ty -> 'b ty_fun -> unit; (*
ext: extends the function with a new case. We must provide a type pattern, (example: List Any). The ty_fun provided is only expected to handle types matching with the pattern. Effectful.
Raises Generic_core_extensible.Pattern_overwrite when called with a type pattern that was already registered.
*)
}
A closure allows us to call a type-indexed consumer and to extend it to new type cases.
val create : string -> 'a closure
create name, creates a new closure initially empty: calling f will raise Type_pattern_match_failure. The name is used in the exception messages. Effectful.