Contents

# Copyright, 2014, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

module Build
	module Graph
		# A call stack contains frames to track state during nested invocations.
		class CallStack
			def initialize
				# Saves state if supplied to #call, which is useful for top level state:
				@frames = [{}.freeze]
			end
			
			# All stack frames which had state associated with them.
			attr :frames
			
			# Yield with the given state, merged with any prior state.
			def with(**state)
				if state and !state.empty?
					@frames << @frames.last.merge(state).freeze
					yield
					@frames.pop
				else
					yield
				end
			end
			
			# The current stack frame state.
			def last
				@frames.last
			end
		end
	end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
build-graph-1.1.0	lib/build/graph/call_stack.rb