Scala: join an iterable of strings

string scala
scala_newbie picture scala_newbie · Nov 23, 2012 · Viewed 139k times · Source

How do I "join" an iterable of strings by another string in Scala?

val thestrings = Array("a","b","c")
val joined = ???
println(joined)

I want this code to output a,b,c (join the elements by ",").

Answer

Brian Agnew picture Brian Agnew · Nov 23, 2012

How about mkString ?

theStrings.mkString(",")

A variant exists in which you can specify a prefix and suffix too.

See here for an implementation using foldLeft, which is much more verbose, but perhaps worth looking at for education's sake.

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