One of the reasons I suggest this now is, that it would be perfect to
introduce such changes in Groovy 3.0: People expect changes, articles
and books with the new syntax are written...
I test switched our project to Groovy 2.5, and the (improved) final
support actual caught 3 places where final variables had been reassigned ;-)
@AutoFinal does not apply to local variables (by (our) design).
"So some advocate omitting the final keyword but coding as if it was
there to obtain more succinct, easier to read code.".
But using "fin" instead of "def" would /actually /use final, while
supplying the exact same amount of succcintness ?-)
Cheers,
mg
On 22.07.2018 08:53, Paul King wrote:
I am probably -1 right now on a new keyword when I think the existing
one works just fine.
One reason some Groovy folks might not use final more frequently is
because it has
historically (up until 2.4.x) been ignored by Groovy for local
variables. Java
also ignores final at runtime for local variables but that doesn't
matter for a statically
compiled language. Have a look at the bytecode using javap -v from
this Java program:
public class Hello {
public void method1() {
final Object o1 = new Object();
}
public void method2() {
Object o2 = new Object();
}
}
You will notice that the bytecode for method1 and method2 is identical.
Groovy 2.5 does a better job of detecting final for local variables.
It does it
in a similar sort of way to Java - at compile time. I'd be inclined to
wait and
see how this added support (plus @AutoFinal) affects usage.
The other discussions I have seen around not using final are around style.
The 'final' modifier is particularly good at stopping the practice of
mutating some
variable mid-way through a long method in a confusing way. Agile practices
discourage long methods, functional style discourages mutating variables
and codenarc can be used to some extent to catch bad behavior. So some
advocate omitting the final keyword but coding as if it was there to
obtain
more succinct, easier to read code. Now that we have @AutoFinal, I am
not sure that we need to aggressively further promote its usage but rather
watch how usage changes in the short term.
Cheers, Paul.
On Sun, Jul 22, 2018 at 7:50 AM MG <[email protected]
<mailto:[email protected]>> wrote:
Hi guys,
I have been wondering for a while whether Groovy developers use "def"
even if a variable is actually is "final" not only because every
Groovy
example code uses "def", but also because "final" as a word is longer
than "def".
Therefore I propose to introduce the shortcut "fin" for "final" in
Groovy.
e.g. to support
class Goo {
fin String name
fin Goo gooParent
Goo(fin String name, fin Goo gooParent) { ... }
String gooGoal(fin x) {
fin y = 2*x
fin int z = x + y
}
}
Cheers,
mg
