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# frozen_string_literal: true
module Parser
class Lexer::StackState
def initialize(name)
@name = name.freeze
clear
end
def clear
@stack = 0
end
def push(bit)
bit_value = bit ? 1 : 0
@stack = (@stack << 1) | bit_value
bit
end
def pop
bit_value = @stack & 1
@stack >>= 1
bit_value == 1
end
def lexpop
@stack = ((@stack >> 1) | (@stack & 1))
@stack[0] == 1
end
def active?
@stack[0] == 1
end
def empty?
@stack == 0
end
def to_s
"[#{@stack.to_s(2)} <= #{@name}]"
end
alias inspect to_s
end
end
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