if I need a function inside another function I can...

# announcements

[enleur]

if I need a function inside another function I can do it in several ways:

val isCool = fun(a: Int) = a > 0
val isCool = { a: Int -> a > 0 }
fun isCool(a: Int) = a > 0

are there any differences or pitfalls?

[dagguh]

enleur: https://medium.com/@BladeCoder/exploring-kotlins-hidden-costs-part-2-324a4a50b70

[arocnies]

https://sites.google.com/a/athaydes.com/renato-athaydes/posts/kotlinshiddencosts-benchmarks

[ilya.gorbunov]

@enleur The difference between first and second form is that unqualified return is allowed inside anonymous fun but not inside lambda.
The third one declares a function isCool, rather than a variable of functional type.

[enleur]

Thank you