dc001a01e5
This PR adds the `binderNameHint` gadget. It can be used in rewrite and
simp rules to preserve a user-provided name where possible.
The expression `binderNameHint v binder e` defined to be `e`.
If it is used on the right-hand side of an equation that is applied by a
tactic like `rw` or `simp`,
and `v` is a local variable, and `binder` is an expression that (after
beta-reduction) is a binder
(so `fun w => …` or `∀ w, …`), then it will rename `v` to the name used
in the binder, and remove
the `binderNameHint`.
A typical use of this gadget would be as follows; the gadget ensures
that after rewriting, the local
variable is still `name`, and not `x`:
```
theorem all_eq_not_any_not (l : List α) (p : α → Bool) :
l.all p = !l.any fun x => binderNameHint x p (!p x) := sorry
example (names : List String) : names.all (fun name => "Waldo".isPrefixOf name) = true := by
rw [all_eq_not_any_not]
-- ⊢ (!names.any fun name => !"Waldo".isPrefixOf name) = true
```
This gadget is supported by `simp`, `dsimp` and `rw` in the
right-hand-side of an equation, but not
in hypotheses or by other tactics.
42 lines
905 B
Text
42 lines
905 B
Text
/-
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Copyright (c) 2014 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Authors: Leonardo de Moura
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-/
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prelude
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import Init.Prelude
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import Init.Notation
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import Init.Tactics
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import Init.TacticsExtra
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import Init.ByCases
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import Init.RCases
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import Init.Core
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import Init.Control
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import Init.Data.Basic
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import Init.WF
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import Init.WFTactics
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import Init.Data
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import Init.System
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import Init.Util
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import Init.Dynamic
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import Init.ShareCommon
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import Init.MetaTypes
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import Init.Meta
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import Init.NotationExtra
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import Init.SimpLemmas
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import Init.PropLemmas
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import Init.Hints
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import Init.Conv
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import Init.Guard
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import Init.Simproc
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import Init.SizeOfLemmas
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import Init.BinderPredicates
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import Init.Ext
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import Init.Omega
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import Init.MacroTrace
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import Init.Grind
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import Init.While
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import Init.Syntax
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import Init.Internal
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import Init.Try
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import Init.BinderNameHint
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