preview

lib/package.rb

@@ -0,0 +1,151 @@
+require 'binding_of_caller'
+
+#
+class Package < Module
+  #
+  module KernelMethods
+    NS_SEP = '/'
+
+    module_function
+
+    # Return the package as a value
+    def import(caller_binding, namespace, as: nil, to: :method)
+      to ||= :value
+
+      send("import_to_#{to}", caller_binding, namespace, as: as)
+    end
+
+    # Return the package as a value
+    def import_to_value(_binding, namespace, as: nil)
+      Package.new(namespace)
+    end
+
+    # Assign the package to a local variable in the caller's binding
+    # Return the package as a value
+    # /!\ Experimental
+    def import_to_local(caller_binding, namespace, as: nil)
+      sym = (as || ns_last(namespace)).to_sym
+      setter = caller_binding.eval(<<-RUBY)
+        #{sym} = nil
+        -> (v) { #{sym} = v }
+      RUBY
+
+      setter.call(Package.new(namespace))
+    end
+
+    # Define a method in the caller's context that hands out the package
+    # Return the package as a value
+    def import_to_method(caller_binding, namespace, as: nil)
+      sym = (as || ns_last(namespace)).to_sym
+      clr = caller_binding.eval('self')
+      setter = clr.instance_eval(<<-RUBY)
+        -> (v) { define_singleton_method(:#{sym}) { v }; v }
+      RUBY
+
+      setter.call(Package.new(namespace))
+    end
+
+    # Set a const to the package in the caller's context
+    # Return the package as a value
+    def import_to_const(caller_binding, namespace, as: nil)
+      sym = (as || ns_classify(ns_last(namespace)).to_sym)
+      clr = caller_binding.eval('self')
+      target = clr.respond_to?(:const_set) ? clr : clr.class
+      setter = target.instance_eval(<<-RUBY)
+        -> (v) { const_set(:#{sym}, v) }
+      RUBY
+
+      setter.call(Package.new(namespace))
+    end
+
+    def ns_from_filename(ns)
+      ns.gsub('/', NS_SEP).gsub(/\.rb$/, '')
+    end
+
+    def ns_to_filename(ns)
+      ns.gsub(NS_SEP, '/') + '.rb'
+    end
+
+    def ns_last(ns)
+      ns.split(NS_SEP).last
+    end
+
+    def ns_classify(namespace)
+      namespace.split(NS_SEP).map! do |v|
+        v.split('_').map!(&:capitalize).join('')
+      end.join('::')
+    end
+  end
+
+  class << self
+    def new(file)
+      file = KernelMethods.ns_to_filename(file)
+      self[file] ||= super(file)
+    end
+
+    def [](key)
+      loaded[key]
+    end
+
+    def []=(key, value)
+      loaded[key] = value
+    end
+
+    def loaded
+      @store ||= {}
+    end
+
+    def delete(ns)
+      @store.delete(ns_to_filename(ns))
+    end
+
+    def reload!
+      @store = {}
+    end
+
+    def path
+      $LOAD_PATH
+    end
+  end
+
+  def initialize(file)
+    @source_file = file
+    @name = KernelMethods.ns_from_filename(file)
+    load_in_module(file)
+  end
+
+  attr_reader :name
+  alias_method :to_s, :name
+
+  def load(file, wrap = false)
+    wrap ? super : load_in_module(File.join(dir, file))
+  rescue Errno::ENOENT
+    super
+  end
+
+  def inspect
+    format("#<#{self.class.name}(#{name}):0x%014x>", object_id)
+  end
+
+  private
+
+  def load_in_module(file)
+    module_eval(IO.read(file),
+                File.expand_path(file))
+  rescue Errno::ENOENT
+    raise
+  end
+
+  def method_added(name)
+    module_function(name)
+  end
+end
+
+#
+module Kernel
+  def import(*args)
+    caller_binding = args.last.is_a?(Binding) ? args.pop : binding.of_caller(1)
+    args.unshift(caller_binding)
+    Package::KernelMethods.import(*args)
+  end
+end