How to map Java overloaded constructors to Frege functions -


java (unfortunately) supports constructors , methods overload. example, hashmap has 4 constructors. in frege can't do:

data map = native java.util.map  data hashmap = native java.util.hashmap     native new :: () -> stmutable s hashmap     native new :: int -> stmutable s hashmap     native new :: int -> float -> stmutable s hashmap     native new :: mutable s map -> stmutable s hashmap

this doesn't compile because can't bind 4 times "new". possible have 4 "java constructors" in frege datatype?

overloaded constructors , methods can defined using |:

data hashmap k v = native java.util.hashmap    native new :: mutable s (map k v) -> stmutable s (hashmap k v)               | () -> stmutable s (hashmap k v)               | int -> stmutable s (hashmap k v)               | int -> float -> stmutable s (hashmap k v)

you can use https://github.com/frege/native-gen starting point generate frege code java class. above code generated using project.

i said starting point because cannot automated. can't determine purity of method , nulls native methods. hence can take generated code , modify purity or make return type maybe a if know method may return null.


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