This PR adds the infrastructure for simproc and discharger DSLs used to
specify `pre`/`post` simproc chains and conditional rewrite dischargers
in `Sym.simp` variants.
**Syntax categories** (`src/Init/Sym/Simp/SimprocDSL.lean`):
- `sym_simproc` with primitives (`ground`, `telescope`, `rewrite`,
`self`, `none`) and combinators (`>>`, `<|>`)
- `sym_discharger` with primitives (`self`, `none`) for the `with`
clause of `rewrite`
**Elaboration attributes**
(`src/Lean/Elab/Tactic/Grind/SimprocDSL.lean`):
- `builtin_sym_simproc` / `sym_simproc` mapping syntax to `Syntax →
GrindTacticM Simproc`
- `builtin_sym_discharger` / `sym_discharger` mapping syntax to `Syntax
→ GrindTacticM Discharger`
- `elabSymSimproc`, `elabSymDischarger`, and `elabWithClause`
dispatchers
Built-in elaborators for each primitive/combinator will follow in a
subsequent PR after the stage0 update.
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
545f27956b