f1707117f0
Specializes the congr lemma generated for the `arg` conv tactic to only rewrite the chosen argument. This makes it much more likely that the chosen argument is able to be accessed. Lets `arg` access the domain and codomain of pi types via `arg 1` and `arg 2` in more situations. Upstreams `pi_congr` for this from mathlib. Adds a negative indexing option, where `arg -2` accesses the second-to-last argument for example, making the behavior of `lhs` available to `arg`. This works for `enter` as well. Other improvement: when there is an error in the `enter [...]` tactic, individual locations get underlined with the error. The tactic info now also is like `rw`, so you can see the intermediate conv states. Closes #5871
68 lines
1.3 KiB
Text
68 lines
1.3 KiB
Text
/-!
|
||
# `congr` conv tactic with "over-applied" functions
|
||
-/
|
||
|
||
/-!
|
||
The function `g` is "over-applied". Previously, conv-mode `congr` failed.
|
||
-/
|
||
/--
|
||
info: case a
|
||
a b : Nat
|
||
g : {α : Type} → α → α
|
||
f : Nat → Nat
|
||
h : a = b
|
||
| f
|
||
|
||
case a
|
||
a b : Nat
|
||
g : {α : Type} → α → α
|
||
f : Nat → Nat
|
||
h : a = b
|
||
| a
|
||
-/
|
||
#guard_msgs in
|
||
example (a b : Nat) (g : {α : Type} → α → α) (f : Nat → Nat) (h : a = b) : g f a = g f b := by
|
||
conv =>
|
||
lhs
|
||
congr
|
||
trace_state
|
||
· rfl
|
||
· rw [h]
|
||
|
||
example (a b : Nat) (g : {α : Type} → α → α) (f : Nat → Nat) (h : a = b) : g f a = g f b := by
|
||
conv =>
|
||
lhs
|
||
arg 2
|
||
rw [h]
|
||
|
||
/-!
|
||
While we are here, test `arg` too via `enter`.
|
||
-/
|
||
|
||
/--
|
||
info: a b : Nat
|
||
g : {α : Type} → α → α
|
||
f : Nat → Nat
|
||
h : a = b
|
||
| a
|
||
---
|
||
info: a b : Nat
|
||
g : {α : Type} → α → α
|
||
f : Nat → Nat
|
||
h : a = b
|
||
| f
|
||
---
|
||
info: a b : Nat
|
||
g : {α : Type} → α → α
|
||
f : Nat → Nat
|
||
h : a = b
|
||
| a
|
||
-/
|
||
#guard_msgs in
|
||
example (a b : Nat) (g : {α : Type} → α → α) (f : Nat → Nat) (h : a = b) : g f a = g f b := by
|
||
conv =>
|
||
conv => enter [1,2]; trace_state
|
||
conv => enter [1,1]; trace_state
|
||
conv => enter [1,@3]; trace_state
|
||
conv => fail_if_success enter [1,@1] -- cannot select the `Type` argument due to dependence.
|
||
rw [h]
|