Speeding up: s += "string"

sik0fewl xxdigitalhellxx at hotmail.com
Tue Apr 15 10:29:35 EDT 2003


Cameron Laird wrote:
> I'm not optimistic.  I'll be more precise:  the problem
> is real, and good solutions are sensitive to data char-
> acteristics.  It's easy to improve performance of the
> s1 += s2 operations that characterize e-mail filtering
> while simultaneously degrading unacceptably the same
> operation embedded in an XML filter.  I am close to
> asserting the conjecture that every solution harms too
> many existing legitimate users.

Just adding my two cents..

People should keep in mind that s += a is shorthand for s = s + a. If you 
look at it the second way you can clearly see that a is appending to s and 
then s is *assigned* that value. In both cases two operations are being done.

Perhaps we could introduce .= as a true assign/append operation. Although 
this would still be a mutable operation, which contradicts the documents.

-- 
Ryan





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