summaryrefslogtreecommitdiff
path: root/lib/rake/scope.rb
diff options
context:
space:
mode:
Diffstat (limited to 'lib/rake/scope.rb')
-rw-r--r--lib/rake/scope.rb42
1 files changed, 42 insertions, 0 deletions
diff --git a/lib/rake/scope.rb b/lib/rake/scope.rb
new file mode 100644
index 0000000..33e1c08
--- /dev/null
+++ b/lib/rake/scope.rb
@@ -0,0 +1,42 @@
+module Rake
+ class Scope < LinkedList
+
+ # Path for the scope.
+ def path
+ map { |item| item.to_s }.reverse.join(":")
+ end
+
+ # Path for the scope + the named path.
+ def path_with_task_name(task_name)
+ "#{path}:#{task_name}"
+ end
+
+ # Trim +n+ innermost scope levels from the scope. In no case will
+ # this trim beyond the toplevel scope.
+ def trim(n)
+ result = self
+ while n > 0 && ! result.empty?
+ result = result.tail
+ n -= 1
+ end
+ result
+ end
+
+ # Scope lists always end with an EmptyScope object. See Null
+ # Object Pattern)
+ class EmptyScope < EmptyLinkedList
+ @parent = Scope
+
+ def path
+ ""
+ end
+
+ def path_with_task_name(task_name)
+ task_name
+ end
+ end
+
+ # Singleton null object for an empty scope.
+ EMPTY = EmptyScope.new
+ end
+end