dest_type

Type.dest_type : hol_type -> string * hol_type list

Breaks apart a non-variable type.

If ty is a type constant, then dest_type ty returns (ty,[]). If ty is a compound type (ty1,...,tyn)tyop, then dest_type ty returns (tyop,[ty1,...,tyn]).

Failure

Fails if ty is a type variable.

Example

> dest_type bool;
val it = ("bool", []): string * hol_type list

> dest_type (alpha --> bool);
val it = ("fun", [“:α”, “:bool”]): string * hol_type list

Comments

A more precise alternative is dest_thy_type, which tells which theory the type operator was declared in.

See also

Type.mk_type, Type.dest_thy_type, Type.dest_vartype