40 lines
1,015 B
Text
40 lines
1,015 B
Text
open nat
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inductive vector (A : Type) : nat → Type :=
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| nil {} : vector A zero
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| cons : Π {n}, A → vector A n → vector A (succ n)
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open vector
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notation a :: b := cons a b
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notation `[` l:(foldr `,` (h t, cons h t) nil `]`) := l
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example (a b : nat) : succ a = succ b → a + 2 = b + 2 :=
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begin
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intro H,
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injection H with p,
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rewrite p
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end
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example (A : Type) (n : nat) (v w : vector A n) (a : A) (b : A) :
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a :: v = b :: w → b = a :=
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begin
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intro H, injection H with neqn aeqb beqw,
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rewrite aeqb
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end
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open prod
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example (A : Type) (a₁ a₂ a₃ b₁ b₂ b₃ : A) : (a₁, a₂, a₃) = (b₁, b₂, b₃) → b₁ = a₁ :=
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begin
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intro H, injection H with a₁b₁ a₂b₂ a₃b₃,
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rewrite a₁b₁
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end
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example (a₁ a₂ a₃ b₁ b₂ b₃ : nat) : (a₁+2, a₂+3, a₃+1) = (b₁+2, b₂+2, b₃+2) → b₁ = a₁ × a₃ = b₃+1 :=
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begin
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intro H, injection H with a₁b₁ sa₂b₂ a₃sb₃,
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esimp at *,
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rewrite [a₁b₁, a₃sb₃], split,
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repeat trivial
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end
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