Raw string literals and Unicode escapes

Jim Laskey james.laskey at oracle.com
Mon Feb 26 21:54:01 UTC 2018


Why introduce an artificial limit? Identifiers don’t have a limit. 3.8. Identifiers An identifier is an unlimited-length sequence of Java letters and Java digits, the first of which must be a Java letter.

— Jim

> On Feb 26, 2018, at 5:29 PM, Maurizio Cimadamore <maurizio.cimadamore at oracle.com> wrote:
> 
> 
> 
> On 26/02/18 20:17, John Rose wrote:
>> Any *finite choice* of end-quotes has the same problem, with
>> a non-zero probability that decreases (but does not vanish)
>> with the number of available end-quotes.  The only way to
>> break out of the box is to allow the user an unlimited range
>> of successively "stronger" end-quotes (i.e., less likely ones).
> In reality there is a 'finite' upper bound for this length, which is given by 2^16 /2 = 2 ^ 15. That's the maximum delimiter size you could encode in a Java String which you can also symmetrically close - and it's an edge case, as it will contain the empty string.
> 
> So, yes, on paper, I agree with the argument, in practice, I guess I'd me more in favor of limiting the number of repetitions - I wouldn't like to open the door to puzzlers:
> 
> `````````````````````````````````````````````````````````````````````````hello`````````````````````````````````````````````````````````````````````````
> 
> (which might leave some Ascii art lovers a bit unhappy :-))
> 
> I think limiting to 8 or some other reasonable small number will probably reduce the clash probability enough? And, even if it's not enough, I guess we'd still be left with the question if a long (possibly unbounded?) escaping sequence is something we'd like to see in Java.
> 
> Maurizio

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