Definition df-base 11970

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 11964	. 2 class Base
2		c1 7626	. . 3 class 1
3	2	cslot 11963	. 2 class Slot 1
4	1, 3	wceq 1331	1 wff Base = Slot 1

This definition is referenced by:  base0  12013  baseval  12016  baseid  12017  basendx  12018  basendxnn  12019  basendxnplusgndx  12070  basendxnmulrndx  12078