Add macos example

Makefile

@@ -2,6 +2,8 @@ current_dir := $(shell pwd)
 CSRCS := $(wildcard tools/xkremap/*.[ch])
 MRBSRCS := $(wildcard mrblib/xkremap/*.rb)
 MRBCSRCS := $(wildcard src/*.[ch])
+# Using master to apply https://github.com/mruby/mruby/pull/3192
+REVISION=0ff3ae1fbaed62010c54c43235e29cdc85da2f78
 .PHONY: all clean
 
 all: xkremap
@@ -13,8 +15,8 @@ xkremap: mruby/build/host/bin/xkremap
 	cp mruby/build/host/bin/xkremap xkremap
 
 mruby:
-	curl -L --fail --retry 3 --retry-delay 1 https://github.com/mruby/mruby/archive/1.2.0.tar.gz -s -o - | tar zxf -
-	mv mruby-1.2.0 $@
+	git clone https://github.com/mruby/mruby
+	git -C mruby reset --hard $(REVISION)
 
 mruby/build/host/bin/xkremap: mruby build_config.rb $(CSRCS) $(MRBSRCS) $(MRBCSRCS)
 	cd mruby && MRUBY_CONFIG="$(current_dir)/build_config.rb" make

examples/macos.rb

@@ -0,0 +1,9 @@
+%w[a z x c v w t].each do |key|
+  remap "Alt-#{key}", to: "C-#{key}"
+end
+
+window class_only: 'google-chrome' do
+  %w[f l].each do |key|
+    remap "Alt-#{key}", to: "C-#{key}"
+  end
+end