sig
val vcompare : Ast.value -> Ast.value -> int
val concat : Ast.environment -> Ast.environment -> Ast.environment
val pattern_match : Ast.value -> Ast.pattern -> bool * Ast.environment
val update : Ast.id -> Ast.value -> Ast.environment -> unit
val eval : Ast.expr -> Ast.environment -> Ast.value
val eval_arith :
Ast.expr ->
Ast.expr -> Ast.environment -> (int -> int -> int) -> Ast.value
val eval_bool :
Ast.expr ->
Ast.expr -> Ast.environment -> (bool -> bool -> bool) -> Ast.value
val eval_comp :
Ast.expr ->
Ast.expr -> Ast.environment -> (int -> int -> bool) -> Ast.value
end