String Find in Scala in Scala

In Scala, you can find the index of a substring using indexOf():

s.indexOf(sub)           // returns index of first occurrence, or -1 if not found
s.lastIndexOf(sub)       // returns index of last occurrence
s.indexOf(sub, fromIdx)  // search starting from index `fromIdx`

Here are some examples:

var sentence = "Hello World"
var idx = sentence.indexOf("World")
println(idx)  // 6

println(sentence.indexOf("xyz"))  // -1  (not found)

The index returned is the position of the first character of the found substring.