1# $NetBSD: varmod.mk,v 1.7 2022/08/24 21:38:06 rillig Exp $ 2# 3# Tests for variable modifiers, such as :Q, :S,from,to or :Ufallback. 4# 5# See also: 6# varparse-errors.mk 7 8# As of 2022-08-06, the possible behaviors during parsing are: 9# 10# * `strict`: the parsing style used by most modifiers: 11# * either uses `ParseModifierPart` or parses the modifier literal 12# * other modifiers may follow, separated by a ':' 13# 14# * `greedy`: calls `ParseModifierPart` with `ch->endc`; this means 15# that no further modifiers are parsed in that expression. 16# 17# * `no-colon`: after parsing this modifier, the following modifier 18# does not need to be separated by a colon. 19# Omitting this colon is bad style. 20# 21# * `individual`: parsing this modifier does not follow the common 22# pattern of calling `ParseModifierPart`. 23# 24# The SysV column says whether a parse error in the modifier falls back 25# trying the `:from=to` System V modifier. 26# 27# | **Operator** | **Behavior** | **Remarks** | **SysV** | 28# |--------------|--------------|--------------------|----------| 29# | `!` | no-colon | | no | 30# | `:=` | greedy | | yes | 31# | `?:` | greedy | | no | 32# | `@` | no-colon | | no | 33# | `C` | no-colon | | no | 34# | `D` | individual | custom parser | N/A | 35# | `E` | strict | | yes | 36# | `H` | strict | | yes | 37# | `L` | no-colon | | N/A | 38# | `M` | individual | custom parser | N/A | 39# | `N` | individual | custom parser | N/A | 40# | `O` | strict | only literal value | no | 41# | `P` | no-colon | | N/A | 42# | `Q` | strict | | yes | 43# | `R` | strict | | yes | 44# | `S` | no-colon | | N/A | 45# | `T` | strict | | N/A | 46# | `U` | individual | custom parser | N/A | 47# | `[` | strict | | no | 48# | `_` | individual | strcspn | yes | 49# | `gmtime` | strict | only literal value | yes | 50# | `hash` | strict | | N/A | 51# | `localtime` | strict | only literal value | yes | 52# | `q` | strict | | yes | 53# | `range` | strict | | N/A | 54# | `sh` | strict | | N/A | 55# | `t` | strict | | no | 56# | `u` | strict | | yes | 57# | `from=to` | greedy | SysV, fallback | N/A | 58 59DOLLAR1= $$ 60DOLLAR2= ${:U\$} 61 62# To get a single '$' sign in the value of a variable expression, it has to 63# be written as '$$' in a literal variable value. 64# 65# See Var_Parse, where it calls Var_Subst. 66.if ${DOLLAR1} != "\$" 67. error 68.endif 69 70# Another way to get a single '$' sign is to use the :U modifier. In the 71# argument of that modifier, a '$' is escaped using the backslash instead. 72# 73# See Var_Parse, where it calls Var_Subst. 74.if ${DOLLAR2} != "\$" 75. error 76.endif 77 78# It is also possible to use the :U modifier directly in the expression. 79# 80# See Var_Parse, where it calls Var_Subst. 81.if ${:U\$} != "\$" 82. error 83.endif 84 85# XXX: As of 2020-09-13, it is not possible to use '$$' in a variable name 86# to mean a single '$'. This contradicts the manual page, which says that 87# '$' can be escaped as '$$'. 88.if ${$$:L} != "" 89. error 90.endif 91 92# In lint mode, make prints helpful error messages. 93# For compatibility, make does not print these error messages in normal mode. 94# Should it? 95.MAKEFLAGS: -dL 96.if ${$$:L} != "" 97. error 98.endif 99 100# A '$' followed by nothing is an error as well. 101.if ${:Uword:@word@${word}$@} != "word" 102. error 103.endif 104 105# The variable modifier :P does not fall back to the SysV modifier. 106# Therefore the modifier :P=RE generates a parse error. 107# XXX: The .error should not be reached since the variable expression is 108# malformed, and this error should be propagated up to Cond_EvalLine. 109VAR= STOP 110.if ${VAR:P=RE} != "STORE" 111. error 112.endif 113 114all: # nothing 115