020da5bffb
This PR fixes an issue when including a hard line break in a `Format` that caused subsequent (ordinary) line breaks to be erroneously flattened to spaces. This issue is especially important for displaying notes and hints in error messages, as these components could appear garbled due to improper line-break rendering.
23 lines
660 B
Text
23 lines
660 B
Text
variable {α : Type _} [Mul α] [Inhabited α]
|
||
|
||
abbrev Left (a : α) : α := a * default
|
||
abbrev Right (a : α): α := default * a
|
||
|
||
theorem mul_comm (a b : α) : a * b = b * a := sorry
|
||
|
||
set_option trace.Meta.Tactic.simp true
|
||
/--
|
||
trace: [Meta.Tactic.simp.rewrite] mul_comm:1000:perm, perm rejected Left a ==> default * a
|
||
[Meta.Tactic.simp.rewrite] mul_comm:1000:perm:
|
||
Right a
|
||
==>
|
||
a * default
|
||
[Meta.Tactic.simp.rewrite] mul_comm:1000:perm, perm rejected a * default ==> default * a
|
||
[Meta.Tactic.simp.rewrite] eq_self:1000:
|
||
Left a = a * default
|
||
==>
|
||
True
|
||
-/
|
||
#guard_msgs in
|
||
example (a : α) : Left a = Right a := by
|
||
simp [mul_comm]
|