JEP-468: Derived record creation in record methods with parameter

[Eirik Bjørsnøs]

Hi,

JEP-468 briefly mentions that derived record expressions can also be used
inside the record class:

Derived record creation expressions can also be used inside record classes
> to simplify the implementation of basic operations:



record Complex(double re, double im) {
>     Complex conjugate() { return this with { im = -im; }; }
>     Complex realOnly()  { return this with { im = 0; }; }
>     Complex imOnly()    { return this with { re = 0; }; }
> }


I'm trying to understand what happens when a derived expression is used in
a record method taking a parameter with the same name as one of the record
components:

record Complex(double re, double im) {
    Complex withReal(double re) { return this with { re = ?; }; }
}

Can "this" be used inside the transformation block, like the following?

     Complex withReal(double re) { return this with { this.re = re; }; }


I know this particular example is a bit silly, but I think it may be
useful to combine multiple transformations in a single record method, also
when the method takes one or more parameters. People will be running into
this.

Perhaps this could be clarified in the JEP with an example or does it
need clarification in the JLS? Or is it just me missing something, as
usual? :-)

Thanks,
Eirik.
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