1# $NetBSD: ternary.mk,v 1.2 2020/10/24 08:34:59 rillig Exp $
2
3all:
4 @for x in "" A= A=42; do ${.MAKE} -f ${MAKEFILE} show $$x; done
5
6show:
7 @echo "The answer is ${A:?known:unknown}"
8 @echo "The answer is ${A:?$A:unknown}"
9 @echo "The answer is ${empty(A):?empty:$A}"
10