What do you mean by this? Is this the same method of declaring inner functions within the scope of the outer function?
Or if you're only doing it once use a lambda (with the same advantages).
I guess the point is that people are starting to discover that languages like Python and JS support these functional idioms quite nicely.
Remember when all the books on JS pretended that it was some kind of crippled cousin of Java (as the name suggests), rather than a Scheme-lite in Java-esque syntax (as its designer has opined).