Metamath Proof Explorer


Theorem curry1f

Description: Functionality of a curried function with a constant first argument. (Contributed by NM, 29-Mar-2008)

Ref Expression
Hypothesis curry1.1 𝐺 = ( 𝐹 ( 2nd ↾ ( { 𝐶 } × V ) ) )
Assertion curry1f ( ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐶𝐴 ) → 𝐺 : 𝐵𝐷 )

Proof

Step Hyp Ref Expression
1 curry1.1 𝐺 = ( 𝐹 ( 2nd ↾ ( { 𝐶 } × V ) ) )
2 ffn ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐹 Fn ( 𝐴 × 𝐵 ) )
3 1 curry1 ( ( 𝐹 Fn ( 𝐴 × 𝐵 ) ∧ 𝐶𝐴 ) → 𝐺 = ( 𝑥𝐵 ↦ ( 𝐶 𝐹 𝑥 ) ) )
4 2 3 sylan ( ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐶𝐴 ) → 𝐺 = ( 𝑥𝐵 ↦ ( 𝐶 𝐹 𝑥 ) ) )
5 fovrn ( ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐶𝐴𝑥𝐵 ) → ( 𝐶 𝐹 𝑥 ) ∈ 𝐷 )
6 5 3expa ( ( ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐶𝐴 ) ∧ 𝑥𝐵 ) → ( 𝐶 𝐹 𝑥 ) ∈ 𝐷 )
7 4 6 fmpt3d ( ( 𝐹 : ( 𝐴 × 𝐵 ) ⟶ 𝐷𝐶𝐴 ) → 𝐺 : 𝐵𝐷 )