Metamath Proof Explorer

Theorem edgfid

Description: Utility theorem: index-independent form of df-edgf . (Contributed by AV, 16-Nov-2021)

Ref Expression
Assertion edgfid 
|- .ef = Slot ( .ef ` ndx )

Proof

Step Hyp Ref Expression
1 df-edgf 
 |-  .ef = Slot ; 1 8
2 1nn0 
 |-  1 e. NN0
3 8nn 
 |-  8 e. NN
4 2 3 decnncl 
 |-  ; 1 8 e. NN
5 1 4 ndxid 
 |-  .ef = Slot ( .ef ` ndx )