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Definition df-iedg 29086
Description: Define the function mapping a graph to its indexed edges. This definition is very general: It defines the indexed edges for any ordered pair as its second component, and for any other class as its "edge function". It is meaningful, however, only if the ordered pair represents a graph resp. the class is an extensible structure (containing a slot for "edge functions") representing a graph. (Contributed by AV, 20-Sep-2020.)
Assertion
Ref Expression
df-iedg iEdg = (𝑔 ∈ V ↦ if(𝑔 ∈ (V × V), (2nd𝑔), (.ef‘𝑔)))

Detailed syntax breakdown of Definition df-iedg
StepHypRef Expression
1 ciedg 29084 . 2 class iEdg
2 vg . . 3 setvar 𝑔
3 cvv 3431 . . 3 class V
42cv 1546 . . . . 5 class 𝑔
53, 3cxp 5616 . . . . 5 class (V × V)
64, 5wcel 2119 . . . 4 wff 𝑔 ∈ (V × V)
7 c2nd 7930 . . . . 5 class 2nd
84, 7cfv 6485 . . . 4 class (2nd𝑔)
9 cedgf 29075 . . . . 5 class .ef
104, 9cfv 6485 . . . 4 class (.ef‘𝑔)
116, 8, 10cif 4454 . . 3 class if(𝑔 ∈ (V × V), (2nd𝑔), (.ef‘𝑔))
122, 3, 11cmpt 5153 . 2 class (𝑔 ∈ V ↦ if(𝑔 ∈ (V × V), (2nd𝑔), (.ef‘𝑔)))
131, 12wceq 1547 1 wff iEdg = (𝑔 ∈ V ↦ if(𝑔 ∈ (V × V), (2nd𝑔), (.ef‘𝑔)))
Colors of variables: wff setvar class
This definition is referenced by:  iedgval  29088
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