Implement target type/pattern-specific variables

For example:

cxx{*-options}: dist = true

1. Only single '*' wildcard is supported, matches 0 or more characters.
2. If target type is not specified, it defaults to any target.
3. Appending (+=) is not allowed.
4. The value is expanded immediately in the context of the scope.
5. The more specific pattern (i.e., with the shortest "stem") is preferred.
   If the stem has the same length, then the last defined (but not redefined)
   pattern is used. This will probably have to change to become an error.

See tests/variable/type-pattern for more examples.

1 files changed, 33 insertions, 0 deletions

diff --git a/tests/variable/type-pattern/buildfile b/tests/variable/type-pattern/buildfile
new file mode 100644
index 0000000..8c353a5
--- /dev/null
+++ b/tests/variable/type-pattern/buildfile
@@ -0,0 +1,33 @@
+#dir/foo{*}: x = y # directory
+#foo{*.*}: x = y # multiple wildcards
+#foo{*}: x = y # unknown target type
+#file{*}: x += y # append
+
+# Use --verbose 6 to examine.
+#
+
+dir{*}: x = y
+
+x = z
+dir{*-foo}: x = $x # 'z'
+
+x = G
+file{*-foo}: x = x
+file{xfoo}: x = $x      # 'G'
+file{-foo}: x = $x      # 'x'
+file{x-foo}: x = $x     # 'x'
+file{bar-*-foo}: x = X
+file{bar-x}: x = $x     # 'G'
+file{bar--foo}: x = $x  # 'X'
+file{bar-x-foo}: x = $x # 'X'
+
+file{*-fox}: x = 1
+file{fox-*}: x = 2
+file{fox-fox}: x = $x # '2'
+file{*-fox}: x = 3
+file{fox-x-fox}: x = $x # still '2'!
+
+*-foz: x = z        # any target
+file{x-foz}: x = $x # 'z'
+
+./: