`simp?` does not work in `conv` mode

Prerequisites

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Description

Trying to use simp? in conv mode gives an error "unexpected identifier; expected command".

Context

simp and simp only are valid tactics in conv mode. So it would be natural if simp? would also work (and allow to replace simp calls by simp only calls for efficiency).

See the discussion on Zulip.

Steps to Reproduce

MWE:

example (n : Nat) : 123 + 2 * n = 123 + (n + n) := by
  conv =>
    enter [1, 2]
    simp? -- error

Expected behavior:

simp? should work in conv mode in the same way as it does normally.

Actual behavior:

simp? in conv mode results in an error.

Versions

Lean 4.15.0-nightly-2024-11-21 Target: x86_64-unknown-linux-gnu

Impact

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leanprover / lean4