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 Since 2020, the `intro` tactic has superceded it.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.
23 lines
434 B
Text
23 lines
434 B
Text
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theorem tst1 (x y z : Nat) : y = z → x = x → x = y → x = z :=
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by {
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intro h1 h2 h3;
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revert h2;
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intro h2;
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exact Eq.trans h3 h1
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}
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theorem tst2 (x y z : Nat) : y = z → x = x → x = y → x = z :=
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by {
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intro h1 h2 h3;
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revert y;
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intro y hb ha;
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exact Eq.trans ha hb
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}
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theorem tst3 (x y z : Nat) : y = z → x = x → x = y → x = z := by
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intros
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revert ‹x = y›
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intro ha
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exact Eq.trans ha ‹y = z›
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