67 

    67 

    68 print(ap.parse("aade"))

    68 print(ap.parse("aade"))

    69 

    69 

    70 val abp = SeqParser(ap, bp)

    70 val abp = SeqParser(ap, bp)

    71 print(abp.parse("abade"))

    71 print(abp.parse("abade"))

    74 print(abp.parse("abc"))

    72 print(abp.parse("abc"))

    75 

    73 

    76 MapParser(abp, ab => s"$ab").parse("abc")

    74 MapParser(abp, ab => s"$ab").parse("abc")

    77 

    75 

    78 // an atomic parser for parsing strings according to a regex

    76 // an atomic parser for parsing strings according to a regex

   177 lazy val T: Parser[String, Int] = {

   175 lazy val T: Parser[String, Int] = {

   178   (F ~ p"*" ~ T).map{ case ((x, _), z) => x * z } || F }

   176   (F ~ p"*" ~ T).map{ case ((x, _), z) => x * z } || F }

   179 lazy val F: Parser[String, Int] = {

   177 lazy val F: Parser[String, Int] = {

   180   (p"(" ~ E ~ p")").map{ case ((_, y), _) => y } || NumParserInt }

   178   (p"(" ~ E ~ p")").map{ case ((_, y), _) => y } || NumParserInt }

   181 

   179 

   183 println(E.parse_all("1+3+4"))

   181 println(E.parse_all("1+3+4"))

   184 println(E.parse("1+3+4"))

   182 println(E.parse("1+3+4"))

   185 println(E.parse_all("4*2+3"))

   183 println(E.parse_all("4*2+3"))

   186 println(E.parse_all("4*(2+3)"))

   184 println(E.parse_all("4*(2+3)"))

   187 println(E.parse_all("(4)*(((2+3)))"))

   185 println(E.parse_all("(4)*(((2+3)))"))