08eb78a5b2
This PR sets up the new integrated test/bench suite. It then migrates all benchmarks and some related tests to the new suite. There's also some documentation and some linting. For now, a lot of the old tests are left alone so this PR doesn't become even larger than it already is. Eventually, all tests should be migrated to the new suite though so there isn't a confusing mix of two systems.
93 lines
2.7 KiB
Text
93 lines
2.7 KiB
Text
import Lean
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/-
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# Nested `let rec` declarations in the presence of delayed metavariable assignments
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https://github.com/leanprover/lean4/issues/6927
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Nested declarations using `let rec` should compile correctly even when nested within expressions
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that are elaborated using delayed metavariable assignments, such as `match` expressions and tactic
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blocks. See the Note [Delayed-Assigned Metavariables in Free Variable Collection] in
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`MutualDef.lean` for additional details.
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-/
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inductive Tree : Type where
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| leaf
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| node (p : Nat) (brs : List Tree)
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def Tree.substNats (M : Tree) (σ : Nat → Nat) : Tree :=
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let rec go M : Tree := match M with
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| .leaf => leaf
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| .node p brs =>
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let rec goList : List Tree → List Tree
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| [] => []
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| M :: Ms => go M :: goList Ms
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.node (σ p) (goList brs)
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go M
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/-
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Previously, free variable dependencies in `inner` were not correctly detected, leading that
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declaration to contain free variables when sent to the kernel.
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-/
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namespace Ex1
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def outer (f : Nat → Nat) :=
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let rec middle n := match n with
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| Nat.zero => 0 | .succ _ =>
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let rec inner := middle n
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f 0
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()
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end Ex1
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/-
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`by` blocks induced behavior similar to the above, since they also produce metavariables during
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elaboration.
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-/
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def tac (f : Nat → Nat) :=
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let rec middle n := by
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let rec inner := middle (Nat.succ n)
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exact f 0
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()
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/- Previously, `inner` was incorrectly compiled as an `axiom`, rendering `outer` noncomputable. -/
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namespace Ex2
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/--
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error: fail to show termination for
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Ex2.outer.middle.inner
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Ex2.outer.middle
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with errors
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failed to infer structural recursion:
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Not considering parameter f of Ex2.outer.middle.inner:
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it is unchanged in the recursive calls
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Not considering parameter f of Ex2.outer.middle:
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it is unchanged in the recursive calls
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Cannot use parameters n✝ of Ex2.outer.middle.inner and n of Ex2.outer.middle:
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failed to eliminate recursive application
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outer.middle f✝ (n + 1)
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Cannot use parameters n of Ex2.outer.middle.inner and n of Ex2.outer.middle:
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failed to eliminate recursive application
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outer.middle f✝ (n + 1)
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Could not find a decreasing measure.
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The basic measures relate at each recursive call as follows:
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(<, ≤, =: relation proved, ? all proofs failed, _: no proof attempted)
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Call from Ex2.outer.middle.inner to Ex2.outer.middle at 89:6-20:
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n✝ n
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n ? ?
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Call from Ex2.outer.middle to Ex2.outer.middle.inner at 91:4-11:
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n
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n✝ _
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n _
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Please use `termination_by` to specify a decreasing measure.
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-/
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#guard_msgs in
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def outer (f : Nat → Nat) (n : Nat) : Nat :=
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let rec middle n : Nat := match n with
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| 0 => 1
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| n + 1 =>
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let rec inner (n : Nat) : Nat :=
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middle (n + 1)
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let _ := f
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inner n
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middle n
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end Ex2
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