In Scala I have a string of the form
val str = "[ab][bc][cd][dx][42]"
What is the most efficient way in Scala, regular expression utilizing or otherwise, to split that string into a Seq[String] that would be of the form:
("ab","bc","cd","dx","42")
Thank you.
You can try this:
val str = "[ab][bc][cd][dx][42]"
val res = str.drop(1).sliding(2, 4).toList
println(res) // List(ab, bc, cd, dx, 42)
val str2 = "[ab]"
val res2 = str2.drop(1).sliding(2, 4).toList
println(res2) // List(ab)
val str3 = ""
val res3 = str3.drop(1).sliding(2, 4).toList
println(res3) // List()
you can try:
str.split("(\\]\\[)|(\\[)|(\\])").filterNot(_.isEmpty)
Mainly using groups (][, ], [) for delimiter and trimming the array.
You can use this regex:
(?<=\[)([^]]+)(?=\])
Code:
scala> val re = "(?<=\\[)([^]]+)(?=\\])".r
re: scala.util.matching.Regex = (?<=\[)([^]]+)(?=\])
scala> for(m <- re.findAllIn("[ab][bc][cd][dx][42]")) println(m)
ab
bc
cd
dx
42
Assuming ][ is the delimiter between any two consecutive items, consider
str.drop(1).dropRight(1).split("\\]\\[")
delivers
Array("ab", "bc", "cd", "dx", "42")
Update
A tiny bit more general an approach, where we define String delimiters,
implicit class Spl(val str: String) extends AnyVal {
def regSplit(leftDel: String, rightDel: String) =
str.stripPrefix(leftDel).stripSuffix(rightDel).split(rightDel+leftDel)
}
Thus
str.regSplit("\\[","\\]")
res: Array[String] = Array([ab, bc, cd, dx, 42])
\[([^\]]+)\]
The easiest and most logical way is to match and not split.Just match and grab the captures or group 1.See demo.
