scala - Splitting string using Regex and pattern matching throws an exception -


could guys please tell me i'm doing incorrectly trying extract using regex pattern-matching? have following code

val pattern = "=".r val pattern(key, value) = "key=value"

and following exception in runtime

exception in thread "main" scala.matcherror: key=value (of class java.lang.string)

that's more of regular expression problem: regex not capture groups, matches single = character.

with

val pattern = "([^=]*)=(.*)".r

you get:

scala> val pattern(key, value) = "key=value" key: string = key value: string = value

edit:

also, won't match if input string empty. can change pattern make match, or (better) can pattern match regex, so:

"key=value" match {    case pattern(k, v) => //     case _ => // wrong input, nothing }

if wanted split input text whatever regex matches, possible using regex.split:

scala> val pattern = "=".r pattern: scala.util.matching.regex = =  scala> val array(key, value) = pattern.split("key=value") key: string = key value: string = value

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