26 lines
495 B
Text
26 lines
495 B
Text
prelude
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precedence `+`:65
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namespace nat
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constant nat : Type.{1}
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constant add : nat → nat → nat
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infixl + := add
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end nat
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namespace int
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open nat (nat)
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constant int : Type.{1}
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constant add : int → int → int
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infixl + := add
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constant of_nat : nat → int
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namespace coercions
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coercion of_nat
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end coercions
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end int
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open nat
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open int
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constants n m : nat
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check n+m -- coercion nat -> int is not available
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open int.coercions
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check n+m -- coercion nat -> int is available
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