// scalatags + −
import ammonite.ops._+ −
+ −
import $ivy.`com.lihaoyi::scalatags:0.8.2` + −
import scalatags.Text.all._+ −
import scalatags.Text._+ −
+ −
// regular expressions including records+ −
abstract class Rexp + −
case object ZERO extends Rexp+ −
case object ONE extends Rexp+ −
case class CHAR(c: Char) extends Rexp+ −
case class ALT(r1: Rexp, r2: Rexp) extends Rexp + −
case class SEQ(r1: Rexp, r2: Rexp) extends Rexp + −
case class STAR(r: Rexp) extends Rexp + −
case class SPECIAL(s: String) extends Rexp+ −
+ −
def nullable (r: Rexp) : Boolean = r match {+ −
case ZERO => false+ −
case ONE => true+ −
case CHAR(_) => false+ −
case ALT(r1, r2) => nullable(r1) || nullable(r2)+ −
case SEQ(r1, r2) => nullable(r1) && nullable(r2)+ −
case STAR(_) => true+ −
}+ −
+ −
def der(c: Char, r: Rexp) : Rexp = r match {+ −
case ZERO => ZERO+ −
case ONE => ZERO+ −
case CHAR(d) => if (c == d) ONE else ZERO+ −
case ALT(r1, r2) => ALT(der(c, r1), der(c, r2))+ −
case SEQ(r1, r2) => + −
if (nullable(r1)) ALT(SEQ(der(c, r1), r2), der(c, r2))+ −
else SEQ(der(c, r1), r2)+ −
case STAR(r1) => SEQ(der(c, r1), STAR(r1))+ −
}+ −
+ −
def ders(s: List[Char], r: Rexp) : Rexp = s match {+ −
case Nil => r+ −
case c::s => ders(s, der(c, r))+ −
}+ −
+ −
def simp(r: Rexp) : Rexp = r match {+ −
case ALT(r1, r2) => (simp(r1), simp(r2)) match {+ −
case (ZERO, r2s) => r2s+ −
case (r1s, ZERO) => r1s+ −
case (r1s, r2s) => if (r1s == r2s) r1s else ALT (r1s, r2s)+ −
}+ −
case SEQ(r1, r2) => (simp(r1), simp(r2)) match {+ −
case (ZERO, _) => ZERO+ −
case (_, ZERO) => ZERO+ −
case (ONE, r2s) => r2s+ −
case (r1s, ONE) => r1s+ −
case (r1s, r2s) => SEQ(r1s, r2s)+ −
}+ −
case r => r+ −
}+ −
+ −
def ders_simp(s: List[Char], r: Rexp) : Rexp = s match {+ −
case Nil => r+ −
case c::s => ders_simp(s, simp(der(c, r)))+ −
}+ −
+ −
+ −
def pp(r: Rexp) : TypedTag[String] = r match {+ −
case CHAR(c) => li(code(c.toString))+ −
case ALT(r1, r2) => li(code("+"), ul(pp(r1), pp(r2)))+ −
case SEQ(r1, r2) => li(code(raw("·")), ul(pp(r1), pp(r2)))+ −
case STAR(r1) => li(code("*"), ul(pp(r1)))+ −
case ZERO => li(code("0"))+ −
case ONE => li(code("1"))+ −
case SPECIAL(s) => li(code(raw(s)))+ −
} + −
+ −
def mktree(r: Rexp) = + −
ul(cls := "tree")(pp(r))+ −
+ −
+ −
def index(rs: List[Rexp]) = + −
html(+ −
head(link(rel := "stylesheet", href := "./style.css")),+ −
body(rs.map(mktree))+ −
)+ −
+ −
+ −
+ −
/*+ −
println(index(List(simple, test, evil2)))+ −
+ −
val simple = CHAR('a')+ −
val test = ALT(CHAR('a'), CHAR('b'))+ −
+ −
+ −
write.over(pwd/"t1.html", + −
index(List(evil2, + −
ders("a".toList, evil2),+ −
ders("aa".toList, evil2),+ −
ders("aaa".toList, evil2))))+ −
*/+ −
+ −
val evil2 = SEQ(STAR(STAR(CHAR('a'))), CHAR('b'))+ −
val r1 = STAR(ALT(SPECIAL("<i>r<sub>1</sub></i>"), SPECIAL("<i>r<sub>2</sub></i>")))+ −
val r2 = ALT(SPECIAL("<i>r<sub>1</sub></i>"), STAR(SPECIAL("<i>r<sub>2</sub></i>")))+ −
+ −
@main+ −
def main(fname: String) = {+ −
val content = index(List(r1))+ −
write.over(pwd / fname, content)+ −
} + −