Hi everybody,
i think there are two ideas that worth think about now that the expression
switch will be released soon that are not related to the elephant in the room,
the pattern matching.
First, a statement switch can use the arrow syntax with an expression that
throw an expression.
switch(x) {
case 10 -> 42;
default -> throw new AssertionError(); // there is no curly braces needed
here
}
but lambdas do not allow throw as an expression.
This is not coherent, i think, we should fill that hole by allowing throw
expression with no curly braces in lambdas (like we already allow function
calls that return void in a lambda).
A question that have came twice at the end of my both talks about the
expression switch is: why there is not arrow syntax for the
try-catch/try-finally/try-with-resources ?
I've not spent a lot of time thinking about it but the syntax for try/catch or
try/finally seems weird
var value =
try -> integer.parseInt(token)
catch(NumberFormatException e) -> 0;
It's a little less weird with a try-with-resources (at least when the is
neither a catch nor a finally)
var text = try(var lines = Files.lines(path)) -> lines.collect(joining("."));
I think we should not try to go in that direction, because the next question
will be what about if/else
var test = if (result == 42) -> true else -> null;
which is just a more verbose way to write a ternary.
regards,
Rémi
