:正規表現で足し算(2).md

http://akouryy.hatenablog.jp/entry/regexp/add-2

add2.rb

require_relative 'check'

ADD2 = %r/
  ^ 0 \+ (?<ZeroPlusB> [01]++) \= \k<ZeroPlusB> $
| ^ (?<APlusZero> [01]++) \+ 0 \= \k<APlusZero> $
|
  (?<B0> (?= (?<a> \d \g<a> \d | \+ \d*? 0 | \d*+ \+ ) \= )){0}
  (?<B1> (?= (?<b> \d \g<b> \d | \+ \d*? 1 ) \= )){0}
  (?<C0> (?= (?<c> \d \g<c> \d | \+ \d++ \= \d*? 0 ) $ )){0}
  (?<C1> (?= (?<d> \d \g<d> \d | \+ \d++ \= \d*? 1 ) $ )){0}
  (?<Carry0> (?= (?: 1 \g<B0> | 0 \g<B1> )*+ (?: 0 \g<B0> | \+ ))){0}
  (?<Carry1> (?= (?: 1 \g<B0> | 0 \g<B1> )*+ 1 \g<B1> )){0}

  (?<YleX>  (?= (?<e> \d \g<e> \d | \d*+ \+ ) \=     )){0}
  (?<ZeqX>  (?= (?<f> \d \g<f> \d | \+ \d++ \=   ) $ )){0}
  (?<ZeqSX> (?= (?<g> \d \g<g> \d | \+ \d++ \= 1 ) $ )){0}
  (?<ZeqY>  (?= (?<h> \d \g<h> \d |         \=   ) $ )){0}
  (?<ZeqSY> (?= (?<i> \d \g<i> \d |         \= 1 ) $ )){0}

  (?<GetD> (?= (?<j> \d \g<j> \d | \+         (?<D> \d+ ) (?= (?<F> \d*+))) \= )){0}
  (?<GetE> (?= (?<k> \d \g<k> \d | \+ \d++ \= (?<E> \d+ ) (?= (?<G> \d*+))) $ )){0}

  (?<EeqD> \g<GetD> (?= (?<l> \d \g<l> \d | \+ \d++ \= \k<D> ) $ )){0}

  (?<EeqSD> \g<GetD> \g<GetE>
    (?= (?<m> \d \g<m> \d | \+ (?= # increment
        \g<ZeqSY>
        (?<n> 1 \g<n> 0 | \k<F> \= 1 ) \k<G> $
      | \g<ZeqY>
        (?<DECommon> (?: (?<DI> \d) (?=
          (?<o> \d \g<o> \d | \k<F> \= \d*? \k<DI> ) \k<G> $
        ))*+)
        0 (?<p> 1 \g<p> 0 | \k<F> \= \k<DECommon> 1 ) \k<G> $
    ) \d*? ) \= )
  ){0}

  ^
  (?: \g<YleX> \g<ZeqX> \g<Carry0> # I
    | \g<YleX> \g<ZeqSX> \g<Carry1> # II
    | \g<EeqD> \g<Carry0> # III
    | \g<EeqSD> \g<Carry1> # IV
  )

  (?: 0 \g<B0> \g<Carry0> \g<C0>
    | 0 \g<B0> \g<Carry1> \g<C1>
    | 0 \g<B1> \g<Carry0> \g<C1>
    | 0 \g<B1> \g<Carry1> \g<C0>
    | 1 \g<B0> \g<Carry0> \g<C1>
    | 1 \g<B0> \g<Carry1> \g<C0>
    | 1 \g<B1> \g<Carry0> \g<C0>
    | 1 \g<B1> \g<Carry1> \g<C1>
  )++
  \+ [01]++ \= [01]++ $
/x

check(
  ADD2: [
    R1.repeated_permutation(2).map{|i,j|
      "%b+%b=%b" % [i, j, i + j]
    },
    [*1..32].repeated_permutation(3).select{|i,j,k| i + j != k }.map{|i,j,k|
      "%b+%b=%b" % [i, j, k]
    },
  ],
)

check.rb

R1 = *0..127

def check t
  t.each do |name, tests|
    reg = eval name.to_s
    tests[0].each do |t|
      if (m = reg =~ t) != 0
        raise "#{name} =~ #{t.inspect} was #{m.inspect}"
      end
    end
    tests[1].each do |t|
      if m = reg =~ t
        raise "#{name} =~ #{t.inspect} was #{m.inspect}"
      end
    end
    puts "succeed: #{name}"
  end
end