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require 'sexp_processor'
##
# Implements the Composite pattern on SexpProcessor. Need we say more?
#
# Yeah... probably. Implements a SexpProcessor of SexpProcessors so
# you can easily chain multiple to each other. At some stage we plan
# on having all of them run +process+ and but only ever output
# something when +generate+ is called, allowing for deferred final
# processing.
class CompositeSexpProcessor < SexpProcessor
##
# The list o' processors to run.
attr_reader :processors
def initialize # :nodoc:
super
@processors = []
end
##
# Add a +processor+ to the list of processors to run.
def <<(processor)
raise ArgumentError, "Can only add sexp processors" unless
SexpProcessor === processor || processor.respond_to?(:process)
@processors << processor
end
##
# Run +exp+ through all of the processors, returning the final
# result.
def process(exp)
@processors.each do |processor|
exp = processor.process(exp)
end
exp
end
def on_error_in(node_type, &block)
@processors.each do |processor|
processor.on_error_in(node_type, &block)
end
end
end
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