Theorem subgrfun 16388

Description: The edge function of a subgraph of a graph whose edge function is actually a function is a function. (Contributed by AV, 20-Nov-2020.)

Assertion

Ref	Expression
subgrfun	|- ( ( Fun (iEdg ` G ) /\ S SubGraph G ) -> Fun (iEdg ` S ) )

Proof of Theorem subgrfun

Step	Hyp	Ref	Expression
1		eqid 2234	. . . 4 |- (Vtx ` S ) = (Vtx ` S )
2		eqid 2234	. . . 4 |- (Vtx ` G ) = (Vtx ` G )
3		eqid 2234	. . . 4 |- (iEdg ` S ) = (iEdg ` S )
4		eqid 2234	. . . 4 |- (iEdg ` G ) = (iEdg ` G )
5		eqid 2234	. . . 4 |- (Edg ` S ) = (Edg ` S )
6	1, 2, 3, 4, 5	subgrprop2 16381	. . 3 |- ( S SubGraph G -> ( (Vtx ` S ) C_ (Vtx ` G ) /\ (iEdg ` S ) C_ (iEdg ` G ) /\ (Edg ` S ) C_ ~P (Vtx ` S ) ) )
7		funss 5376	. . . 4 |- ( (iEdg ` S ) C_ (iEdg ` G ) -> ( Fun (iEdg ` G ) -> Fun (iEdg ` S ) ) )
8	7	3ad2ant2 1046	. . 3 |- ( ( (Vtx ` S ) C_ (Vtx ` G ) /\ (iEdg ` S ) C_ (iEdg ` G ) /\ (Edg ` S ) C_ ~P (Vtx ` S ) ) -> ( Fun (iEdg ` G ) -> Fun (iEdg ` S ) ) )
9	6, 8	syl 14	. 2 |- ( S SubGraph G -> ( Fun (iEdg ` G ) -> Fun (iEdg ` S ) ) )
10	9	impcom 125	1 |- ( ( Fun (iEdg ` G ) /\ S SubGraph G ) -> Fun (iEdg ` S ) )

Syntax hints:   -> wi 4   /\ wa 104   /\ w3a 1005   C_ wss 3214   ~Pcpw 3674   class class class wbr 4114   Fun wfun 5351   ` cfv 5357  Vtxcvtx 16133  iEdgciedg 16134  Edgcedg 16178   SubGraph csubgr 16374

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-14 2208  ax-ext 2216  ax-sep 4233  ax-pow 4292  ax-pr 4327

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ral 2527  df-rex 2528  df-v 2817  df-un 3218  df-in 3220  df-ss 3227  df-pw 3676  df-sn 3700  df-pr 3701  df-op 3703  df-uni 3920  df-br 4115  df-opab 4177  df-xp 4760  df-rel 4761  df-cnv 4762  df-co 4763  df-dm 4764  df-res 4766  df-iota 5317  df-fun 5359  df-fv 5365  df-subgr 16375

This theorem is referenced by:  subgruhgrfun  16389