--- a/src/Pure/Proof/proof_syntax.ML Wed Jul 24 11:57:30 2019 +0200
+++ b/src/Pure/Proof/proof_syntax.ML Wed Jul 24 13:18:15 2019 +0200
@@ -51,7 +51,7 @@
("", paramT --> paramsT, Mixfix.mixfix "_"),
(Lexicon.mark_const "Pure.Appt", [proofT, aT] ---> proofT, mixfix ("(1_ \<cdot>/ _)", [4, 5], 4)),
(Lexicon.mark_const "Pure.AppP", [proofT, proofT] ---> proofT, mixfix ("(1_ \<bullet>/ _)", [4, 5], 4)),
- (Lexicon.mark_const "Pure.MinProof", proofT, Mixfix.mixfix "?")]
+ (Lexicon.mark_const "Pure.MinProof", proofT, Mixfix.mixfix "\<^bold>?")]
|> Sign.add_trrules (map Syntax.Parse_Print_Rule
[(Ast.mk_appl (Ast.Constant "_Lam")
[Ast.mk_appl (Ast.Constant "_Lam0")