Scala: do not use Return in functions


Be careful when you want to sue Return in Scala:
/ Add two ints, and use this method to sum a list
def add(n:Int, m:Int): Int = n + m
def sum(ns: Int*): Int = ns.foldLeft(0)(add)

scala> sum(33, 42, 99)
res0: Int = 174

// Same, using return 
def addR(n:Int, m:Int): Int = return n + m
def sumR(ns: Int*): Int = ns.foldLeft(0)(addR)

scala> sumR(33, 42, 99)
res1: Int = 174
// Inline add and addR
def sum(ns: Int*): Int = ns.foldLeft(0)((n, m) => n + m) // inlined add

scala> sum(33, 42, 99)
res2: Int = 174 // alright

def sumR(ns: Int*): Int = ns.foldLeft(0)((n, m) => return n + m) // inlined addR

scala> sumR(33, 42, 99)
res3: Int = 33 // um.
Source: https://tpolecat.github.io/2014/05/09/return.html


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