47 lines
1.3 KiB
Ruby
47 lines
1.3 KiB
Ruby
require 'continuation' if RUBY_VERSION.to_f >= 1.9
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class Exception
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attr_accessor :continuation
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def restart(&block)
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continuation.call block
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end
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end
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module RaisePlus
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alias :original_raise :raise
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private
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def raise(*args)
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exception = case
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when args.size == 0
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$!.nil? ? RuntimeError.exception : $!
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when args.size == 1 && args[0].is_a?(String)
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RuntimeError.exception(args[0])
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when args.size == 2 && args[0].is_a?(Exception)
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args[0].exception(args[1])
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when args[0].is_a?(Class) && args[0].ancestors.include?(Exception)
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args[0].exception(args[1])
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else
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args[0]
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end
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# passing something other than a String or Exception is illegal, but if someone does it anyway,
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# that object won't have backtrace or continuation methods. in that case, let's pass it on to
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# the original raise, which will reject it
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return super exception unless exception.is_a?(Exception)
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# keep original backtrace if reraising
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exception.set_backtrace(args.size >= 3 ? args[2] : caller) if exception.backtrace.nil?
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blk = callcc do |cc|
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exception.continuation = cc
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super exception
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end
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blk.call unless blk.nil?
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end
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alias :fail :raise
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end
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