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Metamath Proof Explorer

Theorem ffun

Description: A mapping is a function. (Contributed by NM, 3-Aug-1994)

		Ref	Expression
	Assertion	ffun	$⊢ F : A ⟶ B \to Fun F$

Step	Hyp	Ref	Expression
1		ffn	$⊢ F : A ⟶ B \to F Fn A$
2		fnfun	$⊢ F Fn A \to Fun F$
3	1 2	syl	$⊢ F : A ⟶ B \to Fun F$