On February 20, 2014 6:27:42 PM EST, Vladimir Batov
On 02/21/2014 08:31 AM, Edward Diener wrote:
On 2/16/2014 3:56 PM, Vladimir Batov wrote:
I think you have successfully focused on what is needed for a more flexible lexical_cast-like version this time.
I am especially surprised by the fact that its performance seems quite adequate (without any optimization): [snip] tests. On the other hand the test could not be any more straightforward:
double p4 = clock();
for (int k = 0; k < local::num_cycles; ++k) sscanf("12345", "%d", &v);
double p5 = clock();
for (int k = 0; k < local::num_cycles; ++k) boost::lexical_cast<int>("12345");
double p6 = clock();
for (int k = 0; k < local::num_cycles; ++k) boost::convert<int>::from("12345", ccnv).value();
double p7 = clock();
printf("scanf/lcast/convert=%.2f/%.2f/%.2f seconds.\n", (p5 - p4) / CLOCKS_PER_SEC, (p6 - p5) / CLOCKS_PER_SEC, (p7 - p6) / CLOCKS_PER_SEC);
I assume you're timing an optimized build, on which case you are being misled by the optimizer because you're not using the results of the conversions. ___ Rob (Sent from my portable computation engine)