Metamath Proof Explorer


Definition df-bj-cur

Description: Define currying. See also df-cur . (Contributed by BJ, 11-Apr-2020)

Ref Expression
Assertion df-bj-cur
|- curry_ = ( x e. _V , y e. _V , z e. _V |-> ( f e. ( ( x X. y ) -Set-> z ) |-> ( a e. x |-> ( b e. y |-> ( f ` <. a , b >. ) ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccur-
 |-  curry_
1 vx
 |-  x
2 cvv
 |-  _V
3 vy
 |-  y
4 vz
 |-  z
5 vf
 |-  f
6 1 cv
 |-  x
7 3 cv
 |-  y
8 6 7 cxp
 |-  ( x X. y )
9 csethom
 |-  -Set->
10 4 cv
 |-  z
11 8 10 9 co
 |-  ( ( x X. y ) -Set-> z )
12 va
 |-  a
13 vb
 |-  b
14 5 cv
 |-  f
15 12 cv
 |-  a
16 13 cv
 |-  b
17 15 16 cop
 |-  <. a , b >.
18 17 14 cfv
 |-  ( f ` <. a , b >. )
19 13 7 18 cmpt
 |-  ( b e. y |-> ( f ` <. a , b >. ) )
20 12 6 19 cmpt
 |-  ( a e. x |-> ( b e. y |-> ( f ` <. a , b >. ) ) )
21 5 11 20 cmpt
 |-  ( f e. ( ( x X. y ) -Set-> z ) |-> ( a e. x |-> ( b e. y |-> ( f ` <. a , b >. ) ) ) )
22 1 3 4 2 2 2 21 cmpt3
 |-  ( x e. _V , y e. _V , z e. _V |-> ( f e. ( ( x X. y ) -Set-> z ) |-> ( a e. x |-> ( b e. y |-> ( f ` <. a , b >. ) ) ) ) )
23 0 22 wceq
 |-  curry_ = ( x e. _V , y e. _V , z e. _V |-> ( f e. ( ( x X. y ) -Set-> z ) |-> ( a e. x |-> ( b e. y |-> ( f ` <. a , b >. ) ) ) ) )