How to lazy evaluate functions in a sequence in Scala -

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let's have 3 functions in class can return option[file]. looking nice way execute them in order , stop when first function evaluates (similar pick() lazy evaluation), i.e. don't want use nested if-else statements.

abstract class foo() {   def first(): option[file]   def second(): option[file]   def third(): option[file]   def pick(): option[file] = {     seq(first(), second(), third()).find(_.isdefined).map(_.get)   ) }

the parameter option.orelse passed name, can use chain methods:

def pick(): option[file] = first orelse second orelse third

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