Definition df-base 12809

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 12803	. 2 class Base
2		c1 7925	. . 3 class 1
3	2	cslot 12802	. 2 class Slot 1
4	1, 3	wceq 1372	1 wff Base = Slot 1

This definition is referenced by:  base0  12853  baseval  12856  baseid  12857  basendx  12858  basendxnn  12859  basendxnplusgndx  12928  basendxnmulrndx  12937