1# $NetBSD: varmod-loop-varname.mk,v 1.12 2025/01/11 20:54:46 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 '$' is no longer allowed in the 15# variable name. 16# expect+1: In the :@ modifier, the variable name "${:Ubar:S,b,v,}" must not contain a dollar 17.if ${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+" 18. error 19.else 20. error 21.endif 22 23 24# ":::" is a very creative variable name, unlikely to occur in practice. 25# The expression ${\:\:\:} would not work since backslashes can only 26# be escaped in the modifiers, but not in the variable name, therefore 27# the extra indirection via the modifier ':U'. 28.if ${:U1 2 3:@:::@x${${:U\:\:\:}}y@} != "x1y x2y x3y" 29. error 30.endif 31 32 33# "@@" is another creative variable name. 34.if ${:U1 2 3:@\@\@@x${@@}y@} != "x1y x2y x3y" 35. error 36.endif 37 38 39# In extreme cases, even the backslash can be used as variable name. 40# It needs to be doubled though. 41.if ${:U1 2 3:@\\@x${${:Ux:S,x,\\,}}y@} != "x1y x2y x3y" 42. error 43.endif 44 45 46# The variable name can technically be empty, and in this situation 47# the variable value cannot be accessed since the empty "variable" 48# is protected to always return an empty string. 49.if ${:U1 2 3:@@x${}y@} != "xy xy xy" 50. error 51.endif 52 53 54# The :@ modifier resolves the variables from the replacement text once more 55# than expected. In particular, it resolves _all_ variables from the scope, 56# and not only the loop variable (in this case v). 57SRCS= source 58CFLAGS.source= before 59ALL_CFLAGS:= ${SRCS:@src@${CFLAGS.${src}}@} # note the ':=' 60CFLAGS.source+= after 61.if ${ALL_CFLAGS} != "before" 62. error 63.endif 64 65 66# In the following example, the modifier ':@' expands the '$$' to '$'. This 67# means that when the resulting expression is evaluated, these resulting '$' 68# will be interpreted as starting a subexpression. 69# 70# The d means direct reference, the i means indirect reference. 71RESOLVE= ${RES1} $${RES1} 72RES1= 1d${RES2} 1i$${RES2} 73RES2= 2d${RES3} 2i$${RES3} 74RES3= 3 75 76.if ${RESOLVE:@v@w${v}w@} != "w1d2d3w w2i3w w1i2d3 2i\${RES3}w w1d2d3 2i\${RES3} 1i\${RES2}w" 77. error 78.endif 79 80 81# Until 2020-07-20, the variable name of the :@ modifier could end with one 82# or two dollar signs, which were silently ignored. 83# There's no point in allowing a dollar sign in that position. 84# Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the 85# variable name. 86# expect+1: In the :@ modifier, the variable name "v$" must not contain a dollar 87.if ${1 2 3:L:@v$@($v)@} != "(1) (2) (3)" 88. error 89.else 90. error 91.endif 92# expect+1: In the :@ modifier, the variable name "v$$" must not contain a dollar 93.if ${1 2 3:L:@v$$@($v)@} != "() () ()" 94. error 95.else 96. error 97.endif 98# expect+1: In the :@ modifier, the variable name "v$$$" must not contain a dollar 99.if ${1 2 3:L:@v$$$@($v)@} != "() () ()" 100. error 101.else 102. error 103.endif 104 105 106# It may happen that there are nested :@ modifiers that use the same name for 107# for the loop variable. These modifiers influence each other. 108# 109# As of 2020-10-18, the :@ modifier is implemented by actually setting a 110# variable in the scope of the expression and deleting it again after the 111# loop. This is different from the .for loops, which substitute the 112# expression with ${:Uvalue}, leading to different unwanted side effects. 113# 114# To make the behavior more predictable, the :@ modifier should restore the 115# loop variable to the value it had before the loop. This would result in 116# the string "1a b c1 2a b c2 3a b c3", making the two loops independent. 117.if ${:U1 2 3:@i@$i${:Ua b c:@i@$i@}${i:Uu}@} != "1a b cu 2a b cu 3a b cu" 118. error 119.endif 120 121# During the loop, the variable is actually defined and nonempty. 122# If the loop were implemented in the same way as the .for loop, the variable 123# would be neither defined nor nonempty since all expressions of the form 124# ${var} would have been replaced with ${:Uword} before evaluating them. 125.if defined(var) 126. error 127.endif 128.if ${:Uword:@var@${defined(var):?def:undef} ${empty(var):?empty:nonempty}@} \ 129 != "def nonempty" 130. error 131.endif 132.if defined(var) 133. error 134.endif 135 136all: .PHONY 137