7fa1a8b114
This PR eliminates uses of `intros x y z` (with arguments) and updates the `intros` docstring to suggest that `intro x y z` should be used instead. The `intros` tactic is historical, and can be traced all the way back to Lean 2, when `intro` could only introduce a single hypothesis. Since 2020, the `intro` tactic has superceded it. The `intros` tactic (without arguments) is currently still useful.
24 lines
650 B
Text
24 lines
650 B
Text
--
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set_option trace.Meta.Tactic.subst true
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theorem tst1 (x y z : Nat) : y = z → x = x → x = y → x = z := by
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intro h1 h2 h3
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subst x
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assumption
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theorem tst2 (x y z : Nat) : y = z → x = z + y → x = z + z := by
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intro h1 h2
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subst h1
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subst h2
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exact rfl
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def BV (n : Nat) : Type := { a : Array Bool // a.size = n }
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theorem tst3 (n m : Nat) (v : BV n) (w : BV m) (h1 : n = m) (h2 : forall (v1 v2 : BV n), v1 = v2) : v = cast (congrArg BV h1.symm) w := by
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subst h1
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apply h2
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theorem tst4 (n m : Nat) (v : BV n) (w : BV m) (h1 : n = m) (h2 : forall (v1 v2 : BV n), v1 = v2) : v = cast (congrArg BV h1.symm) w := by
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subst n
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apply h2
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