Definition df-base 13409

Description: Define the base set (also called underlying set, ground set, carrier set, or carrier) extractor for extensible structures. (Contributed by NM, 4-Sep-2011.) (Revised by Mario Carneiro, 14-Aug-2015.)

Assertion

Ref	Expression
df-base	⊢ Base = Slot 1

Detailed syntax breakdown of Definition df-base

Step	Hyp	Ref	Expression
1		cbs 13403	. 2 class Base
2		c1 8181	. . 3 class 1
3	2	cslot 13402	. 2 class Slot 1
4	1, 3	wceq 1402	1 wff Base = Slot 1

This definition is used by:  base0  13453  baseval  13456  baseid  13457  basendx  13458  basendxnn  13459  basendxnplusgndx  13530  basendxnmulrndx  13539