Timeline for Help understanding the working of Function Objects?
Current License: CC BY-SA 2.5
12 events
| when toggle format | what | by | license | comment | |
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| Feb 1, 2011 at 4:28 | comment | added | Nav | @Donotalo: I didn't suspect that '&' may be a problem. Will remember your cautionary note whenever I work with it though. Thanks :) | |
| Jan 31, 2011 at 12:29 | comment | added | Donotalo | @Nav, yes. :) also the '&' may cause trouble depending on what you're doing with the state machine. | |
| Jan 31, 2011 at 10:53 | comment | added | Nav | @Donotalo: Ok, you're referring to my use of 'const'? I agree with you then :) | |
| Jan 31, 2011 at 10:06 | comment | added | Donotalo | @Nav: not this case. but consider this: en.wikipedia.org/wiki/Function_object#Maintaining_state | |
| Jan 31, 2011 at 9:32 | comment | added | Nav | @Donotalo: I don't see how I'm using the function as a state machine. The function object isn't transitioning at any time. | |
| Jan 31, 2011 at 7:39 | comment | added | Donotalo | @Nav: if you use the function object as state machine, your approach won't work. | |
| Jan 31, 2011 at 6:35 | comment | added | Nav | Thanks. I figured the best way to have the parameters of sort_ints would have been void sort_ints(int* begin_items, int num_items, const ComparisonFunctor& c); | |
| Jan 31, 2011 at 6:23 | vote | accept | Nav | ||
| Jan 31, 2011 at 6:13 | comment | added | templatetypedef |
@Nav- The compiler is usually really good at aggressively optimizing the receiver object out of the picture when invoking operator(). Coupled with the fact that the compiler can resolve which function is being called at compile-time (since it knows the type of the receiver), it's often much faster to use function objects than raw functions! (Though it does make the executable bigger)
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| Jan 31, 2011 at 6:01 | comment | added | Tony Delroy | @Nav: yes - a reference would be better. But, a comparison object rarely has much state, and is only passed once regardless of the number of items being sorted, so it's not likely to be a big deal. | |
| Jan 31, 2011 at 5:55 | comment | added | Nav | Does that mean that the third parameter of sort_ints is actually taking an entire object by value? Won't that be bad/inefficient if we're working with large objects? | |
| Jan 31, 2011 at 5:43 | history | answered | templatetypedef | CC BY-SA 2.5 |