Detailed syntax breakdown of Definition df-fg
| Step | Hyp | Ref
 | Expression | 
| 1 |   | cfg 14096 | 
. 2
class
filGen | 
| 2 |   | vw | 
. . 3
setvar 𝑤 | 
| 3 |   | vx | 
. . 3
setvar 𝑥 | 
| 4 |   | cvv 2763 | 
. . 3
class
V | 
| 5 | 2 | cv 1363 | 
. . . 4
class 𝑤 | 
| 6 |   | cfbas 14095 | 
. . . 4
class
fBas | 
| 7 | 5, 6 | cfv 5258 | 
. . 3
class
(fBas‘𝑤) | 
| 8 | 3 | cv 1363 | 
. . . . . 6
class 𝑥 | 
| 9 |   | vy | 
. . . . . . . 8
setvar 𝑦 | 
| 10 | 9 | cv 1363 | 
. . . . . . 7
class 𝑦 | 
| 11 | 10 | cpw 3605 | 
. . . . . 6
class 𝒫
𝑦 | 
| 12 | 8, 11 | cin 3156 | 
. . . . 5
class (𝑥 ∩ 𝒫 𝑦) | 
| 13 |   | c0 3450 | 
. . . . 5
class
∅ | 
| 14 | 12, 13 | wne 2367 | 
. . . 4
wff (𝑥 ∩ 𝒫 𝑦) ≠ ∅ | 
| 15 | 5 | cpw 3605 | 
. . . 4
class 𝒫
𝑤 | 
| 16 | 14, 9, 15 | crab 2479 | 
. . 3
class {𝑦 ∈ 𝒫 𝑤 ∣ (𝑥 ∩ 𝒫 𝑦) ≠ ∅} | 
| 17 | 2, 3, 4, 7, 16 | cmpo 5924 | 
. 2
class (𝑤 ∈ V, 𝑥 ∈ (fBas‘𝑤) ↦ {𝑦 ∈ 𝒫 𝑤 ∣ (𝑥 ∩ 𝒫 𝑦) ≠ ∅}) | 
| 18 | 1, 17 | wceq 1364 | 
1
wff filGen =
(𝑤 ∈ V, 𝑥 ∈ (fBas‘𝑤) ↦ {𝑦 ∈ 𝒫 𝑤 ∣ (𝑥 ∩ 𝒫 𝑦) ≠ ∅}) |