Does anyone know how to get the (Scala part only) desugared translation of a for/comprehension expression before it actually tries to compile in the REPL (or compiler)?
The only thing I've found so far is the compiler "-print" flag but that gives you the full Scala translation…
As I already said in the other topic, scalac -print
prints out scala code, not java. It translates all scala keywords that are not directly compatible with java to normal scala code. It is not possible to let the compiler translate only parts afaik. But basically a for-comprehension is always translated the same way.
A simple for/yield like this
for(x <- List(1,2,3)) yield x*x
will be translated to
List(1,2,3).map {x => x*x}
And without yield
for(x <- List(1,2,3)) println(x)
to
List(1,2,3).foreach{x => println(x)}
Nested fors will be translated to nested flatMap/map constructs
for(x <- List(1,2,3); y <- List(4,5,6)) yield x*y
will be translated to
List(1,2,3).flatMap { x =>
List(4,5,6).map { y =>
x*y
}
}
So there is absolutely no magic