Definition df-gdlop4

Description: Define the fourth Gödel operation. This function takes two arguments and returns the first argument restricted to the second argument (see df-res ). Based on the fourth case of Definition 14.2 of TakeutiZaring p. 144. (Contributed by BTernaryTau, 2-Sep-2026)

	Ref	Expression
Assertion	df-gdlop4	Could not format assertion : No typesetting found for |- ~F4 = ( x e. _V , y e. _V |-> ( x |` y ) ) with typecode |-

Detailed syntax breakdown

Step	Hyp	Ref	Expression
0		cgdlop4	Could not format ~F4 : No typesetting found for class ~F4 with typecode class
1		vx	$$setvarx$$
2		cvv	$$class\mathrm{V}$$
3		vy	$$setvary$$
4	1	cv	$$setvarx$$
5	3	cv	$$setvary$$
6	4 5	cres	$$class\left({x\upharpoonright }_y\right)$$
7	1 3 2 2 6	cmpo	$$class\left(x\in \mathrm{V},y\in \mathrm{V}⟼{x\upharpoonright }_y\right)$$
8	0 7	wceq	Could not format ~F4 = ( x e. _V , y e. _V |-> ( x |` y ) ) : No typesetting found for wff ~F4 = ( x e. _V , y e. _V |-> ( x |` y ) ) with typecode wff