Metamath Proof Explorer


Theorem rabbidva2

Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Thierry Arnoux, 4-Feb-2017)

Ref Expression
Hypothesis rabbidva2.1 φ x A ψ x B χ
Assertion rabbidva2 φ x A | ψ = x B | χ

Proof

Step Hyp Ref Expression
1 rabbidva2.1 φ x A ψ x B χ
2 1 abbidv φ x | x A ψ = x | x B χ
3 df-rab x A | ψ = x | x A ψ
4 df-rab x B | χ = x | x B χ
5 2 3 4 3eqtr4g φ x A | ψ = x B | χ