Re: Pointer vs Reference

Joshua Cranmer <Pidgeot18@xxxxxxxxxxx> writes:

In Java, it really is a pointer. The JLS actually specifically says
that reference values are pointers, as Stefan pointed out.

Probably refering to
"The reference values (often just /references/) are /pointers/ to these
objects, and a special null reference, which refers to no object."
- JLS 4.3.1

However, the JLS doesn't say what a "pointer" *is*, so that doesn't make
us any wiser. It has to be taken as merely informal explanation.

The word "pointer" is used in a few places around the JLS:

6.8.7:
"... Abbreviations, as in buf holding a pointer to a buffer of
some kind ..."

15.13.2
"because the embedded assignment of 2 to index occurs before the check
for a null pointer."

and ofcourse in the index:
"pointers
See references"
and
"pointer, 42" - referencing the first quote.

I.e., the JLS identifies references and "pointers", so saying that
references are pointers is trivial and vacuous.

/L
--
Lasse Reichstein Nielsen - lrn@xxxxxxxxxx
DHTML Death Colors: <URL:http://www.infimum.dk/HTML/rasterTriangleDOM.html>
'Faith without judgement merely degrades the spirit divine.'
.

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