1# $NetBSD: varmod-loop-varname.mk,v 1.4 2021/12/05 15:01:04 rillig Exp $ 2# 3# Tests for the first part of the variable modifier ':@var@...@', which 4# contains the variable name to use during the loop. 5 6# Force the test results to be independent of the default value of this 7# setting, which is 'yes' for NetBSD's usr.bin/make but 'no' for the bmake 8# distribution and pkgsrc/devel/bmake. 9.MAKE.SAVE_DOLLARS= yes 10 11 12# Before 2021-04-04, the name of the loop variable could be generated 13# dynamically. There was no practical use-case for this. 14# Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the 15# variable name. 16.if ${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+" 17. error 18.else 19. error 20.endif 21 22 23# ":::" is a very creative variable name, unlikely to occur in practice. 24# The expression ${\:\:\:} would not work since backslashes can only 25# be escaped in the modifiers, but not in the variable name, therefore 26# the extra indirection via the modifier ':U'. 27.if ${:U1 2 3:@:::@x${${:U\:\:\:}}y@} != "x1y x2y x3y" 28. error 29.endif 30 31 32# "@@" is another creative variable name. 33.if ${:U1 2 3:@\@\@@x${@@}y@} != "x1y x2y x3y" 34. error 35.endif 36 37 38# In extreme cases, even the backslash can be used as variable name. 39# It needs to be doubled though. 40.if ${:U1 2 3:@\\@x${${:Ux:S,x,\\,}}y@} != "x1y x2y x3y" 41. error 42.endif 43 44 45# The variable name can technically be empty, and in this situation 46# the variable value cannot be accessed since the empty "variable" 47# is protected to always return an empty string. 48.if ${:U1 2 3:@@x${}y@} != "xy xy xy" 49. error 50.endif 51 52 53# The :@ modifier resolves the variables from the replacement text once more 54# than expected. In particular, it resolves _all_ variables from the scope, 55# and not only the loop variable (in this case v). 56SRCS= source 57CFLAGS.source= before 58ALL_CFLAGS:= ${SRCS:@src@${CFLAGS.${src}}@} # note the ':=' 59CFLAGS.source+= after 60.if ${ALL_CFLAGS} != "before" 61. error 62.endif 63 64 65# In the following example, the modifier ':@' expands the '$$' to '$'. This 66# means that when the resulting expression is evaluated, these resulting '$' 67# will be interpreted as starting a subexpression. 68# 69# The d means direct reference, the i means indirect reference. 70RESOLVE= ${RES1} $${RES1} 71RES1= 1d${RES2} 1i$${RES2} 72RES2= 2d${RES3} 2i$${RES3} 73RES3= 3 74 75.if ${RESOLVE:@v@w${v}w@} != "w1d2d3w w2i3w w1i2d3 2i\${RES3}w w1d2d3 2i\${RES3} 1i\${RES2}w" 76. error 77.endif 78 79 80# Until 2020-07-20, the variable name of the :@ modifier could end with one 81# or two dollar signs, which were silently ignored. 82# There's no point in allowing a dollar sign in that position. 83# Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the 84# variable name. 85.if ${1 2 3:L:@v$@($v)@} != "(1) (2) (3)" 86. error 87.else 88. error 89.endif 90.if ${1 2 3:L:@v$$@($v)@} != "() () ()" 91. error 92.else 93. error 94.endif 95.if ${1 2 3:L:@v$$$@($v)@} != "() () ()" 96. error 97.else 98. error 99.endif 100 101 102# It may happen that there are nested :@ modifiers that use the same name for 103# for the loop variable. These modifiers influence each other. 104# 105# As of 2020-10-18, the :@ modifier is implemented by actually setting a 106# variable in the scope of the expression and deleting it again after the 107# loop. This is different from the .for loops, which substitute the variable 108# expression with ${:Uvalue}, leading to different unwanted side effects. 109# 110# To make the behavior more predictable, the :@ modifier should restore the 111# loop variable to the value it had before the loop. This would result in 112# the string "1a b c1 2a b c2 3a b c3", making the two loops independent. 113.if ${:U1 2 3:@i@$i${:Ua b c:@i@$i@}${i:Uu}@} != "1a b cu 2a b cu 3a b cu" 114. error 115.endif 116 117# During the loop, the variable is actually defined and nonempty. 118# If the loop were implemented in the same way as the .for loop, the variable 119# would be neither defined nor nonempty since all expressions of the form 120# ${var} would have been replaced with ${:Uword} before evaluating them. 121.if defined(var) 122. error 123.endif 124.if ${:Uword:@var@${defined(var):?def:undef} ${empty(var):?empty:nonempty}@} \ 125 != "def nonempty" 126. error 127.endif 128.if defined(var) 129. error 130.endif 131 132all: .PHONY 133