Release Name: 0.3

Notes: ======== Version 0.3 ============================================================== The biggest change in version 0.3 is that the argument type architecture is now pluggable. Users can add their own typed argument parsers. Along with doing that, I have added file argument types: < - A file that will be read > - A file that will be written to << - A file that will be read in by readlines >> - A file that will be appended to >? - A file that will be written to but the user is prompted if it already exists >>? - A file that will be appended to but the user is prompted if the file doesn't exist Lastly I added the ability to use a block argument to the Usage call so that clean-up of objects created during parsing can be safely cleaned-up at the end of the usage block. The simplest example to illustrate all of the above attributes is a very short copy program that has much more error checking (nice pretty error checking) than your average short ruby copy script. require "usage" Usage.new "<infile >outfile" do |u| u.outfile.write(u.infile.read) end A more complex example (taken from the actual built-in writable file code) is shows how you can add a type of your own: # # This example is taken from the built-in class for arguments that are writable files # that don't want to be overwritten # # first define the file exists exception class class FileOutputExistsError < UsageMod::Error attr_reader :filename def initialize(filename) @filename = filename super("output file exists: '#{filename}'") end end # next define the argument parser plugin class FileOutputQueryPlugin < UsageMod::ArgumentParserPlugin def initialize(usage_ui, str) if FileTest.exist?(str) then raise FileOutputExistsError.new(str) if usage_ui.ask_yes_no(OVERWRITE_QUERY % str, NO_RESPONSE) == NO_RESPONSE end @value = File.open(str, "w") end def close @value.close end end # lastly attach that parser to the character sequence '>?' UsageMod::Base.add_type_handler(">?", FileOutputQueryPlugin) After putting the above code into a library that you require, you do the following: require "usage" require "mycustomtype" Usage.new "<infile >?outfile" do |u| u.outfile.write(u.infile.read) end Check out the README for a complete description of the how usage works.