X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?p=subdirmk.git;a=blobdiff_plain;f=README;h=d750cb8e6daa40c7a6baf84f95bcdf6e699cd402;hp=5e78187942da813ac76be9ff07b9c9cada4cd232;hb=f52334abf79af4ead3ad1a101a104db61ab07162;hpb=fd49f563108abb6cdb9806344be415b656208334

diff --git a/README b/README
index 5e78187..d750cb8 100644
--- a/README
+++ b/README
@@ -93,8 +93,8 @@ zonk' in lib will fail.  If you want to make a target exist
 everywhere, += it with nothing in Prefix.sd.mk or Suffix.sd.mk (see
 below).
 
-Prefix.sd.mk, Suffix.sd.mk, inclusion
--------------------------------------
+Prefix.sd.mk, Suffix.sd.mk, Final.sd.mk, inclusion
+--------------------------------------------------
 
 The files Prefix.sd.mk and Suffix.sd.mk in the toplevel of the source
 are automatically processed before and after each individual
@@ -112,6 +112,9 @@ autogenerated `main.mk' which merely has some basic settings and
 includes.  So if you want to get in early and set global variables,
 put them near the top of Subdir.sd.mk.
 
+The file Final.sd.mk in the toplevel directory is processed and
+included after all the other files.
+
 subdirmk's filter script itself sets (only) these variables:
   top_srcdir
   abs_top_srcdir
@@ -149,7 +152,7 @@ There are two kinds of template files.
  How to include           `&:include foo.sd.mk'   `include foo.mk'
 			  in all relevant .sd.mk  in only one
                           (but not needed for     Subdir.sd.mk
-                           Prefix, Suffix)
+                           Prefix, Suffix, Final)
 
 If you `include subdirmk/regen.mk', dependency management and
 automatic regeneration for all of this template substitution, and for
@@ -251,7 +254,7 @@ So pathname syntax is a subset of:
 &&		=>	&&		for convenience in shell runes
 
 &\&		=>	&		general escaping mechanism
-&\$		=>	$
+&\$		=>	$		provided for $-doubling regimes
 &\NEWLINE				eats the newline and vanishes
 
 &$VARIABLE	=>	$(sub_dir_VARIABLE)	or $(TOP_VARIABLE)
@@ -320,6 +323,25 @@ So pathname syntax is a subset of:
 	`all' is extra special: every directory has an `all'
 	target, which corresponds to &TARGETS.
 
+
+Dollar doubling and macro assistance
+------------------------------------
+
+&$+		Starts dollar-doubling
+&$-		Stops dollar-doubling
+	Both are idempotent and local to the file or context.
+
+While dollar-doubling:
+- - - - - - - - - - -
+
+$	=>	$$	including $'s produced by other
+			 &-expansions not mentioned here
+
+&\$	=>	$
+&$NN	=>	$(NN)	where N are digits
+&$(	=>	$(
+
+
 Subdirectory and variable naming
 --------------------------------