11 lines
361 B
Text
11 lines
361 B
Text
axiom addz {A : Type} [has_add A] [has_zero A] : ∀ a : A, a + 0 = a
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example {A : Type} [has_add A] [has_zero A] (a b c : A) : (a + 0) + (b + 0) + (c + 0) = a + b + c :=
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begin
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repeat {rw addz}
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end
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example {A : Type} [has_add A] [has_zero A] (a b c : A) : (a + 0) + (b + 0) + (c + 0) = a + b + c :=
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begin
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repeat {rw addz, trace "------", trace_state}
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end
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