1# $NetBSD: varmod-loop.mk,v 1.2 2020/08/16 12:30:45 rillig Exp $
2#
3# Tests for the :@var@...${var}...@ variable modifier.
4
5all: mod-loop-varname
6all: mod-loop-resolve
7all: mod-loop-varname-dollar
8all: mod-loop-dollar
9
10# In the :@ modifier, the name of the loop variable can even be generated
11# dynamically.  There's no practical use-case for this, and hopefully nobody
12# will ever depend on this, but technically it's possible.
13# Therefore, in -dL mode, this is forbidden, see lint.mk.
14mod-loop-varname:
15	@echo :${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@:Q}:
16	# ":::" is a very creative variable name, unlikely in practice
17	# The expression ${\:\:\:} would not work since backslashes can only
18	# be escaped in the modifiers, but not in the variable name.
19	@echo :${:U1 2 3:@:::@x${${:U\:\:\:}}y@}:
20	# "@@" is another creative variable name.
21	@echo :${:U1 2 3:@\@\@@x${@@}y@}:
22	# Even "@" works as a variable name since the variable is installed
23	# in the "current" scope, which in this case is the one from the
24	# target.
25	@echo :$@: :${:U1 2 3:@\@@x${@}y@}: :$@:
26	# In extreme cases, even the backslash can be used as variable name.
27	# It needs to be doubled though.
28	@echo :${:U1 2 3:@\\@x${${:Ux:S,x,\\,}}y@}:
29
30# The :@ modifier resolves the variables a little more often than expected.
31# In particular, it resolves _all_ variables from the context, and not only
32# the loop variable (in this case v).
33#
34# The d means direct reference, the i means indirect reference.
35RESOLVE=	${RES1} $${RES1}
36RES1=		1d${RES2} 1i$${RES2}
37RES2=		2d${RES3} 2i$${RES3}
38RES3=		3
39
40mod-loop-resolve:
41	@echo $@:${RESOLVE:@v@w${v}w@:Q}:
42
43# Until 2020-07-20, the variable name of the :@ modifier could end with one
44# or two dollar signs, which were silently ignored.
45# There's no point in allowing a dollar sign in that position.
46mod-loop-varname-dollar:
47	@echo $@:${1 2 3:L:@v$@($v)@:Q}.
48	@echo $@:${1 2 3:L:@v$$@($v)@:Q}.
49	@echo $@:${1 2 3:L:@v$$$@($v)@:Q}.
50
51# Demonstrate that it is possible to generate dollar characters using the
52# :@ modifier.
53#
54# These are edge cases that could have resulted in a parse error as well
55# since the $@ at the end could have been interpreted as a variable, which
56# would mean a missing closing @ delimiter.
57mod-loop-dollar:
58	@echo $@:${:U1:@word@${word}$@:Q}:
59	@echo $@:${:U2:@word@$${word}$$@:Q}:
60	@echo $@:${:U3:@word@$$${word}$$$@:Q}:
61	@echo $@:${:U4:@word@$$$${word}$$$$@:Q}:
62	@echo $@:${:U5:@word@$$$$${word}$$$$$@:Q}:
63	@echo $@:${:U6:@word@$$$$$${word}$$$$$$@:Q}:
64