Theorem ffun

Description: A mapping is a function. (Contributed by NM, 3-Aug-1994) (Proof shortened by Umit Teoman Dogan, 10-Jun-2026)

	Ref	Expression
Assertion	ffun	⊢ ( 𝐹 : 𝐴 ⟶ 𝐵 → Fun 𝐹 )

Proof

Step	Hyp	Ref	Expression
1		ffn	⊢ ( 𝐹 : 𝐴 ⟶ 𝐵 → 𝐹 Fn 𝐴 )
2	1	fnfund	⊢ ( 𝐹 : 𝐴 ⟶ 𝐵 → Fun 𝐹 )