X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?p=subdirmk.git;a=blobdiff_plain;f=README;h=d85a68804c4e4bf8adff2480fc37fcf9bcef0ed7;hp=2f1a1ce4ae4f1ba66813fac327f36db73a9a6112;hb=2c8db0f89fdcb949f0e8f82a223bca194a7a28c8;hpb=f2f72a3200b1d81fa84232c03834addbe1bc3547

diff --git a/README b/README
index 2f1a1ce..d85a688 100644
--- a/README
+++ b/README
@@ -174,10 +174,11 @@ So pathname syntax is a subset of:
 	by the final warning state after processing all the toplevel
 	input files (including Final.sd.mk).
 
-&:local+global [&]VARIABLE ...
-	Suppresses the warning about seeing both VARIABLE and
-	&VARIABLE.  Any & specified in the RHS is redundant: this
-	always affects both versions identically.
+&:local+global [!][&]VARIABLE ...
+	Suppresses any warnings relating to forthcoming mentions
+	to VARIABLE or &VARIABLE, as applicable.  Scope ends at
+	the end of the current directory's Suffix.sd.mk.
+	Prefixing with ! removes [&]VARIABLE from the suppresion list.
 
 &:changequote NEWQUOTE
 	changes the escape sequence from & to literally NEWQUOTE
@@ -218,9 +219,10 @@ STUFF $ THINGS	..	STUFF $$ THINGS
 &:endm		..	endef
 	NAME is processed for &
 
-&${..$..} =>	${eval ${call ..$$..}}
+&{..$..}	=>	${eval ${call ..$$..}}
 	(matches { } pairs to find the end)
 	content is $-doubled (unless it contains &$- to turn that off)
+	cf &(...), see "Convenience syntax for eval", below.
 
 Together &:macro and &${...} provide a more reasonable macro facility
 than raw make.  They solve the problem that make expansions cannot
@@ -244,6 +246,18 @@ A few contexts do not support $-doubling, such as directive arguments
 or places where this might imply $-quadrupling.  (There is no way to
 get $-quadrupling.)
 
+Convenience syntax for eval
+- - - - - - - - - - - - - -
+
+&(thing		=>	$(call thing
+&( thing	=>	$(call thing
+	and specially:
+&(&lc		=>	$(call sub_dir_lc	or $(call TOP_lc
+&( &lc		=>	$(call sub_dir_lc	or $(call TOP_lc
+	even though lc would normally be thought a filename
+
+Unlike &{...}, this does not involve any dollar-doubling.
+
 
 Invocation, "recursive" per-directory targets
 ---------------------------------------------