f89ed40618
This introduces the `ArgsPacker` module and abstraction, to replace the exising `PackDomain`/`PackMutual` code. The motivation was that we now have more uses besides `Fix.lean` (`GuessLex` and `FunInd`), and the code was spread in various places. The goals are * consistent function naming withing the the `PSigma` handling, the `PSum` handling, and the combined interface * avoid taking a type apart just based on the `PSigma`/`PSum` nesting, to be robust in case the user happens to be using `PSigma`/`PSum` somewhere. Therefore, always pass an `arity` or `numFuncs` or `varNames` around. * keep all the `PSigma`/`PSum` encoding logic contained within one module (`ArgsPacker`), and keep that module independent of its users (so no `EqnInfos` visible here). * pick good variable names when matching on a packed argument * the unary function now is either called `fun1._unary` or `fun1._mutual`, never `fun1._unary._mutual`. This file has less heavy dependencies than `PackMutual` had, so build parallelism is improved as well.
77 lines
1.4 KiB
Text
77 lines
1.4 KiB
Text
namespace Ex1
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mutual
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def f : Nat → α → α → α
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| 0, a, b => a
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| n, a, b => g a n b |>.1
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termination_by n _ _ => (n, 2)
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decreasing_by
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simp_wf
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apply Prod.Lex.right
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decide
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def g : α → Nat → α → (α × α)
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| a, 0, b => (a, b)
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| a, n, b => (h a b n, a)
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termination_by _ n _ => (n, 1)
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decreasing_by
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simp_wf
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apply Prod.Lex.right
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decide
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def h : α → α → Nat → α
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| _a, b, 0 => b
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| a, b, n+1 => f n a b
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termination_by _ _ n => (n, 0)
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decreasing_by
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simp_wf
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apply Prod.Lex.left
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apply Nat.lt_succ_self
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end
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#eval f 5 'a' 'b'
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#print f
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#print g
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#print h
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#print f._mutual
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end Ex1
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namespace Ex2
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mutual
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def f : Nat → α → α → α
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| 0, a, b => a
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| n, a, b => g a n b |>.1
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termination_by n _ _ => (n, 2)
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def g : α → Nat → α → (α × α)
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| a, 0, b => (a, b)
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| a, n, b => (h a b n, a)
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termination_by _ n _ => (n, 1)
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def h : α → α → Nat → α
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| a, b, 0 => b
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| a, b, n+1 => f n a b
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termination_by _ _ n => (n, 0)
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end
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#print f._mutual
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end Ex2
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namespace Ex3
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mutual
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def f : Nat → α → α → α
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| 0, a, b => a
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| n, a, b => g a n b |>.1
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def g : α → Nat → α → (α × α)
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| a, 0, b => (a, b)
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| a, n, b => (h a b n, a)
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def h : α → α → Nat → α
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| a, b, 0 => b
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| a, b, n+1 => f n a b
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end
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#print f._mutual
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end Ex3
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