Naked dot - accessing object fields through unqualified "." [C1]

Derek Foster vapor1 at
Sat Mar 28 19:42:05 PDT 2009

The major problem I have with this proposal is that it does not address the point of why I use a prefix on field names. As such, I would still continue to use a prefix even if this proposal were implemented.

In short, I use a prefix to avoid typographical mistakes, like this one:

void setFoo(Thing foob) { // Typo! = foo;

This will compile, and no warnings are produced, but it ends up assigning foo to itself, which is not what was intended.

Your proposal has exactly the same problem:

void setFoo(Thing foob) { // Typo!
    .foo = foo;

It therefore does not substitute for a field prefix, which WILL fix the problem:

void setFoo(Thing foob) { // Typo!
    _foo = foo; // ERROR! Undefined variable 'foo'.

So unless you had some way to make use of the dot prefix mandatory and the only legal way to access fields (which I would like, but which would be an extremely backwards-incompatible change that will never happen in Java), I don't see that adding an optional dot prefix helps the situation except to reduce typing in constructor and setter methods slightly.

(Note: I would love a "self-assignment is forbidden" change to Java. If I have time after my other proposals, I might write one up. (Anyone else want to volunteer? This one is easy!) I might be willing to forego prefixes and use the " = foo" approach, or even the ".foo = foo" approach, if I was sure it wouldn't cause me to fall into the self-assignment trap.)


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