Matching against a regular expression in Scala

Question

I fairly frequently match strings against regular expressions. In Java:

java.util.regex.Pattern.compile(\"\\w+\").matcher(\"this_is\").matches

Ouch. Scala has

Answer 1

You can define a pattern like this :

scala> val Email = """(\w+)@([\w\.]+)""".r

findFirstIn will return Some[String] if it matches or else None.

scala> Email.findFirstIn("test@example.com")
res1: Option[String] = Some(test@example.com)

scala> Email.findFirstIn("test")
rest2: Option[String] = None

You could even extract :

scala> val Email(name, domain) = "test@example.com"
name: String = test
domain: String = example.com

Finally, you can also use conventional String.matches method (and even recycle the previously defined Email Regexp :

scala> "david@example.com".matches(Email.toString)
res6: Boolean = true

Hope this will help.