 @@ -1,194 +1,215 @@
-# $Id: modmisc.mk,v 1.23 2020/07/26 11:39:55 rillig Exp $
+# $Id: modmisc.mk,v 1.24 2020/07/26 12:18:11 rillig Exp $
+#
 # miscellaneous modifier tests
 # do not put any dirs in this list which exist on some
 # but not all target systems - an exists() check is below.
 path=:/bin:/tmp::/:.:/no/such/dir:.
 # strip cwd from path.
 MOD_NODOT=S/:/ /g:N.:ts:
 # and decorate, note that $'s need to be doubled. Also note that
 # the modifier_variable can be used with other modifiers.
 MOD_NODOTX=S/:/ /g:N.:@d@'$$d'@
 # another mod - pretend it is more interesting
 MOD_HOMES=S,/home/,/homes/,
 MOD_OPT=@d@$${exists($$d):?$$d:$${d:S,/usr,/opt,}}@
 MOD_SEP=S,:, ,g
 all:	modvar modvarloop modsysv mod-HTE emptyvar undefvar
 all:	mod-subst
 all:	mod-regex
 all:	mod-loop-varname mod-loop-resolve mod-loop-varname-dollar
 all:	mod-subst-dollar mod-loop-dollar
 all:	mod-regex-limits
 all:	mod-regex-errors
 all:	mod-assign
 all:	mod-assign-nested
 all:	mod-tu-space
 all:	mod-quote
 all:	mod-break-many-words
 # See also sysv.mk.
 modsysv:
 	@echo "The answer is ${libfoo.a:L:libfoo.a=42}"
 # Demonstrates modifiers that are given indirectly from a variable.
 modvar:
 	@echo "path='${path}'"
 	@echo "path='${path:${MOD_NODOT}}'"
 	@echo "path='${path:S,home,homes,:${MOD_NODOT}}'"
 	@echo "path=${path:${MOD_NODOTX}:ts:}"
 	@echo "path=${path:${MOD_HOMES}:${MOD_NODOTX}:ts:}"
 .for d in ${path:${MOD_SEP}:N.} /usr/xbin
 path_$d?= ${d:${MOD_OPT}:${MOD_HOMES}}/
 paths+= ${d:${MOD_OPT}:${MOD_HOMES}}
 .endfor
 modvarloop:
 	@echo "path_/usr/xbin=${path_/usr/xbin}"
 	@echo "paths=${paths}"
 	@echo "PATHS=${paths:tu}"
 PATHNAMES=	a/b/c def a.b.c a.b/c a a.a .gitignore a a.a
 mod-HTE:
 	@echo "dirname of '"${PATHNAMES:Q}"' is '"${PATHNAMES:H:Q}"'"
 	@echo "basename of '"${PATHNAMES:Q}"' is '"${PATHNAMES:T:Q}"'"
 	@echo "suffix of '"${PATHNAMES:Q}"' is '"${PATHNAMES:E:Q}"'"
 	@echo "root of '"${PATHNAMES:Q}"' is '"${PATHNAMES:R:Q}"'"
 # When a modifier is applied to the "" variable, the result is discarded.
 emptyvar:
 	@echo S:${:S,^$,empty,}
 	@echo C:${:C,^$,empty,}
 	@echo @:${:@var@${var}@}
 # The :U modifier turns even the "" variable into something that has a value.
 # The resulting variable is empty, but is still considered to contain a
 # single empty word. This word can be accessed by the :S and :C modifiers,
 # but not by the :@ modifier since it explicitly skips empty words.
 undefvar:
 	@echo S:${:U:S,^$,empty,}
 	@echo C:${:U:C,^$,empty,}
 	@echo @:${:U:@var@empty@}
 WORDS=		sequences of letters
 # FIXME: The "*" in "letters" must not be substituted because of the 1.
 .if ${WORDS:S,e,*,1} != "s*quences of l*tters"
 .warning ${WORDS:S,e,*,1}
 .endif
 .if ${WORDS:S,e,*,} != "s*quences of l*tters"
 .error oops
 .endif
 .if ${WORDS:S,e,*,g} != "s*qu*nc*s of l*tt*rs"
 .error oops
 .endif
 .if ${WORDS:S,^sequ,occurr,} != "occurrences of letters"
 .error oops
 .endif
 .if ${WORDS:S,^of,with,} != "sequences with letters"
 .error oops
 .endif
 .if ${WORDS:S,^office,does not match,} != ${WORDS}
 .error oops
 .endif
 mod-subst:
 	@echo $@:
 	@echo :${:Ua b b c:S,a b,,:Q}:
 	@echo :${:Ua b b c:S,a b,,1:Q}:
 	@echo :${:Ua b b c:S,a b,,W:Q}:
 	@echo :${:Ua b b c:S,b,,g:Q}:
 	@echo :${:U1 2 3 1 2 3:S,1 2,___,Wg:S,_,x,:Q}:
 	@echo ${:U12345:S,,sep,g:Q}
 mod-regex:
 	@echo $@:
 	@echo :${:Ua b b c:C,a b,,:Q}:
 	@echo :${:Ua b b c:C,a b,,1:Q}:
 	@echo :${:Ua b b c:C,a b,,W:Q}:
 	@echo :${:Uword1 word2:C,****,____,g:C,word,____,:Q}:
 	@echo :${:Ua b b c:C,b,,g:Q}:
 	@echo :${:U1 2 3 1 2 3:C,1 2,___,Wg:C,_,x,:Q}:
 # In the :@ modifier, the name of the loop variable can even be generated
 # dynamically.  There's no practical use-case for this, and hopefully nobody
 # will ever depend on this, but technically it's possible.
 mod-loop-varname:
 	@echo :${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@:Q}:
 # The :@ modifier resolves the variables a little more often than expected.
 # In particular, it resolves _all_ variables from the context, and not only
 # the loop variable (in this case v).
+#
 # The d means direct reference, the i means indirect reference.
 RESOLVE=	${RES1} $${RES1}
 RES1=		1d${RES2} 1i$${RES2}
 RES2=		2d${RES3} 2i$${RES3}
 RES3=		3
 mod-loop-resolve:
 	@echo $@:${RESOLVE:@v@w${v}w@:Q}:
 # Until 2020-07-20, the variable name of the :@ modifier could end with one
 # or two dollar signs, which were silently ignored.
 # There's no point in allowing a dollar sign in that position.
 mod-loop-varname-dollar:
 	@echo $@:${1 2 3:L:@v$@($v)@:Q}.
 	@echo $@:${1 2 3:L:@v$$@($v)@:Q}.
 	@echo $@:${1 2 3:L:@v$$$@($v)@:Q}.
 # No matter how many dollar characters there are, they all get merged
 # into a single dollar by the :S modifier.
 mod-subst-dollar:
 	@echo $@:${:U1:S,^,$,:Q}:
 	@echo $@:${:U2:S,^,$$,:Q}:
 	@echo $@:${:U3:S,^,$$$,:Q}:
 	@echo $@:${:U4:S,^,$$$$,:Q}:
 	@echo $@:${:U5:S,^,$$$$$,:Q}:
 	@echo $@:${:U6:S,^,$$$$$$,:Q}:
 	@echo $@:${:U7:S,^,$$$$$$$,:Q}:
 	@echo $@:${:U8:S,^,$$$$$$$$,:Q}:
 # This generates no dollar at all:
 	@echo $@:${:UU8:S,^,${:U$$$$$$$$},:Q}:
 # Here is an alternative way to generate dollar characters.
 # It's unexpectedly complicated though.
 	@echo $@:${:U:range=5:ts\x24:C,[0-9],,g:Q}:
 # Demonstrate that it is possible to generate dollar characters using the
 # :@ modifier.
+#
 # These are edge cases that could have resulted in a parse error as well
 # since the $@ at the end could have been interpreted as a variable, which
 # would mean a missing closing @ delimiter.
 mod-loop-dollar:
 	@echo $@:${:U1:@word@${word}$@:Q}:
 	@echo $@:${:U2:@word@$${word}$$@:Q}:
 	@echo $@:${:U3:@word@$$${word}$$$@:Q}:
 	@echo $@:${:U4:@word@$$$${word}$$$$@:Q}:
 	@echo $@:${:U5:@word@$$$$${word}$$$$$@:Q}:
 	@echo $@:${:U6:@word@$$$$$${word}$$$$$$@:Q}:
 mod-regex-limits:
 	@echo $@:00-ok:${:U1 23 456:C,..,\0\0,:Q}
 	@echo $@:11-missing:${:U1 23 456:C,..,\1\1,:Q}
 	@echo $@:11-ok:${:U1 23 456:C,(.).,\1\1,:Q}
 	@echo $@:22-missing:${:U1 23 456:C,..,\2\2,:Q}
 	@echo $@:22-missing:${:U1 23 456:C,(.).,\2\2,:Q}
 	@echo $@:22-ok:${:U1 23 456:C,(.)(.),\2\2,:Q}
 	# The :C modifier only handles single-digit capturing groups,
 	# which is more than enough for daily use.
 	@echo $@:capture:${:UabcdefghijABCDEFGHIJrest:C,(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)(.),\9\8\7\6\5\4\3\2\1\0\10\11\12,}
 mod-regex-errors:
 	@echo $@: ${UNDEF:Uvalue:C,[,,}
 # Just a bit of basic code coverage for the obscure ::= assignment modifiers.
 mod-assign:
 	@echo $@: ${1 2 3:L:@i@${FIRST::?=$i}@} first=${FIRST}.
 	@echo $@: ${1 2 3:L:@i@${LAST::=$i}@} last=${LAST}.
 	@echo $@: ${1 2 3:L:@i@${APPENDED::+=$i}@} appended=${APPENDED}.
 	@echo $@: ${echo.1 echo.2 echo.3:L:@i@${RAN::!=${i:C,.*,&; & 1>\&2,:S,., ,g}}@} ran:${RAN}.
 	# The assignments happen in the global scope and thus are
 	# preserved even after the shell command has been run.
 	@echo $@: global: ${FIRST:Q}, ${LAST:Q}, ${APPENDED:Q}, ${RAN:Q}.
 mod-assign-nested:
 	@echo $@: ${1:?${THEN1::=then1${IT1::=t1}}:${ELSE1::=else1${IE1::=e1}}}${THEN1}${ELSE1}${IT1}${IE1}
 	@echo $@: ${0:?${THEN2::=then2${IT2::=t2}}:${ELSE2::=else2${IE2::=e2}}}${THEN2}${ELSE2}${IT2}${IE2}
 	@echo $@: ${SINK3:Q}
 	@echo $@: ${SINK4:Q}
 SINK3:=	${1:?${THEN3::=then3${IT3::=t3}}:${ELSE3::=else3${IE3::=e3}}}${THEN3}${ELSE3}${IT3}${IE3}
 SINK4:=	${0:?${THEN4::=then4${IT4::=t4}}:${ELSE4::=else4${IE4::=e4}}}${THEN4}${ELSE4}${IT4}${IE4}
 mod-tu-space:
 	# The :tu and :tl modifiers operate on the variable value
 	# as a single string, not as a list of words. Therefore,
 	# the adjacent spaces are preserved.
 	@echo $@: ${a   b:L:tu:Q}
 mod-quote:
 	@echo $@: new${.newline:Q}${.newline:Q}line
 # Cover the bmake_realloc in brk_string.
 mod-break-many-words:
 	@echo $@: ${UNDEF:U:range=500:[#]}