tests: Test &TARGETS feature

[subdirmk.git] / README

diff --git a/README b/README
index 4da40911ce83909e880874de657b6d4db797992b..fd10056368dfdf7d5679b8440c64d2649cb46395 100644 (file)
--- a/README
+++ b/README
@@ -251,6 +251,9 @@ So pathname syntax is a subset of:
 &\&            =>      &               general escaping mechanism
 &\$            =>      $
 
+&$VARIABLE     =>      $(sub_dir_VARIABLE)     or $(TOP_VARIABLE)
+       VARIABLE is ASCII starting with a letter and matching \w+
+
 & thing thing... &
 &^ thing thing... &
 &~ thing thing... &
@@ -265,9 +268,10 @@ So pathname syntax is a subset of:
        recognised at start of line only (possibly after lwsp)
        args are processed for &
 
-&:include filename             filename should usually be foo.sd.mk
+&:include filename             filename should usually be [&]foo.sd.mk
 &:-include filename            tolerate nonexistent file
        filenames are relative to $(top_srcdir)
+       RHS is &-expanded
 
 &!<lwsp>       disables & until EOL (and then disappears)
 
@@ -291,7 +295,8 @@ So pathname syntax is a subset of:
                NEWQUOTE:changequote &  set escape back to &
 
 &TARGETS_things
-       Handled specially.  If mentioned, declares that this
+       Handled specially.  If mentioned at the start of a line
+       (possibly following whitespace), declares that this
        subdir ought to have a target `things'.  The rule will be
                &/things:: $(&TARGETS_things)
 
@@ -305,9 +310,9 @@ So pathname syntax is a subset of:
        which recursively implies this directory's `things'.
 
        Must be spelled exactly &TARGETS_things.  &_TARGETS_things,
-       for example, is not magic.  But mentioning &TARGETS_things in
-       a #-comment *does* work because the & filter does not care
-       about comments.
+       for example, is not magic.  To make the target exist
+       without providing any prerequisites for it, write a line
+       containing just `&TARGETS_things +='.
 
        `all' is extra special: every directory has an `all'
        target, which corresponds to &TARGETS.