support command-line variables - close #51

lib/rscons.rb

@@ -55,6 +55,11 @@ module Rscons
     #   Whether to output ANSI color escape sequences.
     attr_accessor :do_ansi_color
 
+    # @since 1.16.0
+    # @return [VarSet]
+    #   Access any variables set on the rscons command-line.
+    attr_reader :vars
+
     # Remove all generated files.
     #
     # @return [void]
@@ -232,6 +237,7 @@ module Rscons
   end
 
   @n_threads = determine_n_threads
+  @vars = VarSet.new
 
 end
 

lib/rscons/cli.rb

@@ -60,6 +60,12 @@ module Rscons
 
         end.parse!(argv)
 
+        argv.each do |arg|
+          if arg =~ /^([^=]+)=(.*)$/
+            Rscons.vars[$1] = $2
+          end
+        end
+
         if rsconsfile
           unless File.exists?(rsconsfile)
             $stderr.puts "Cannot read #{rsconsfile}"