1 files changed, 42 insertions, 0 deletions
diff --git a/core/src/main/scala/com/rockymadden/stringmetric/Alphabet.scala b/core/src/main/scala/com/rockymadden/stringmetric/Alphabet.scala
new file mode 100755
index 0000000..5e666d2
--- /dev/null
+++ b/core/src/main/scala/com/rockymadden/stringmetric/Alphabet.scala
@@ -0,0 +1,42 @@
+package com.rockymadden.stringmetric
+
+import scala.collection.immutable.Set
+
+object Alphabet {
+	sealed abstract class AlphabetSet(val chars: Set[Char]) {
+		def isSuperset(a: Char): Boolean = chars.contains(a)
+
+		def isSuperset(a: Array[Char]): Boolean = a.length > 0 && a.takeWhile(chars.contains).length == a.length
+
+		def isSuperset(a: String): Boolean = isSuperset(a.toCharArray)
+	}
+
+
+	case object LowercaseConsonant extends AlphabetSet(
+		Set('b', 'c', 'd', 'f', 'g', 'h', 'j', 'k', 'l', 'm', 'n', 'p', 'q', 'r', 's', 't', 'v', 'w', 'x' ,'z')
+	)
+
+	case object UppercaseConsonant extends AlphabetSet(
+		Set('B', 'C', 'D', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'V', 'W', 'X' ,'Z')
+	)
+
+	case object Consonant extends AlphabetSet(LowercaseConsonant.chars ++ UppercaseConsonant.chars)
+
+	case object LowercaseVowel extends AlphabetSet(Set('a', 'e', 'i', 'o', 'u'))
+
+	case object UppercaseVowel extends AlphabetSet(Set('A', 'E', 'I', 'O', 'U'))
+
+	case object Vowel extends AlphabetSet(LowercaseVowel.chars ++ UppercaseVowel.chars)
+
+	case object LowercaseY extends AlphabetSet(Set('y'))
+
+	case object UppercaseY extends AlphabetSet(Set('Y'))
+
+	case object Y extends AlphabetSet(LowercaseY.chars ++ UppercaseY.chars)
+
+	case object LowercaseAlpha extends AlphabetSet(LowercaseConsonant.chars ++ LowercaseVowel.chars ++ LowercaseY.chars)
+
+	case object UppercaseAlpha extends AlphabetSet(UppercaseConsonant.chars ++ UppercaseVowel.chars ++ UppercaseY.chars)
+
+	case object Alpha extends AlphabetSet(LowercaseAlpha.chars ++ UppercaseAlpha.chars)
+}