12 lines
204 B
Text
12 lines
204 B
Text
def f : nat → option nat → nat
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| a none := a
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| a (some b) := a + b
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example (a b : nat) : f a b = a + b :=
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rfl
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example (a b : nat) : f a b = f a (some b) :=
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rfl
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example : f 1 (1:nat) = 2 :=
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rfl
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