forked from Isabelle_DOF/Isabelle_DOF
68 lines
1.9 KiB
Plaintext
68 lines
1.9 KiB
Plaintext
(* Little theory implementing the an assertion command in Isabelle/HOL. *)
|
|
|
|
theory Assert
|
|
imports Main
|
|
keywords "assert" ::thy_decl
|
|
|
|
begin
|
|
|
|
|
|
ML{*
|
|
|
|
(* Reimplementation needed because not exported from ML structure Value_Command *)
|
|
fun value_maybe_select some_name =
|
|
case some_name
|
|
of NONE => Value_Command.value
|
|
| SOME name => Value_Command.value_select name;
|
|
|
|
(* Reimplementation structure Value_Command due to tiny modification of value_cmd. *)
|
|
|
|
fun assert_cmd some_name modes raw_t state =
|
|
let
|
|
val ctxt = Toplevel.context_of state;
|
|
val t = Syntax.read_term ctxt raw_t;
|
|
val t' = value_maybe_select some_name ctxt t;
|
|
val ty' = Term.type_of t';
|
|
val ty' = case ty' of @{typ "bool"} => ty' | _ => error "Assertion expressions must be boolean.";
|
|
val t' = case t' of @{term "True"} => t' | _ => error "Assertion failed.";
|
|
val ctxt' = Variable.auto_fixes t' ctxt;
|
|
val p = Print_Mode.with_modes modes (fn () =>
|
|
Pretty.block [Pretty.quote (Syntax.pretty_term ctxt' t'), Pretty.fbrk,
|
|
Pretty.str "::", Pretty.brk 1, Pretty.quote (Syntax.pretty_typ ctxt' ty')]) ();
|
|
in Pretty.writeln p end;
|
|
|
|
*}
|
|
|
|
ML{*
|
|
(* Reimplementation needed because not exported from ML structure Value_Command *)
|
|
val opt_modes =
|
|
Scan.optional (@{keyword "("} |-- Parse.!!! (Scan.repeat1 Parse.name --| @{keyword ")"})) [];
|
|
|
|
(* Reimplementation needed because not exported from ML structure Value_Command *)
|
|
val opt_evaluator =
|
|
Scan.option (@{keyword "["} |-- Parse.name --| @{keyword "]"})
|
|
|
|
(* NEW *)
|
|
val _ =
|
|
Outer_Syntax.command @{command_keyword assert} "evaluate and print term"
|
|
(opt_evaluator -- opt_modes -- Parse.term
|
|
>> (fn ((some_name, modes), t) => Toplevel.keep (assert_cmd some_name modes t) ));
|
|
*}
|
|
|
|
|
|
(* Test:
|
|
|
|
assert ""
|
|
assert "3 = 4"
|
|
assert "False"
|
|
assert "5 * 5 = 25 "
|
|
|
|
*)
|
|
|
|
assert "True \<and> True "
|
|
|
|
assert "(5::int) * 5 = 25 "
|
|
|
|
|
|
end
|
|
|