projects / ceph.git / blame
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| 2 | <head> | |
| 3 | <!-- Generated by the Spirit (http://spirit.sf.net) QuickDoc --> | |
| 4 | <title>Efficiency</title> | |
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| 14 | <td width="85%"> | |
| 15 | <font size="6" face="Verdana, Arial, Helvetica, sans-serif"><b>Efficiency</b></font> | |
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| 26 | </tr> | |
| 27 | </table> | |
| 28 | <p> | |
| 29 | Now this is important. Operators that form expressions and statements, while truly expressive, should be used judiciously and sparingly. While aggressive compiler optimizations and inline code helps a lot to produce tighter and faster code, lazy operators and statements will always have more overhead compared to lazy- functions and bound simple functors especially when the logic gets to be quite complex. It is not only run-time code that hits a penalty, complex expressions involving lazy-operators and lazy- functions are also much more difficult to parse and compile by the host C++ compiler and results in much longer compile times.</p> | |
| 30 | <table width="80%" border="0" align="center"> | |
| 31 | <tr> | |
| 32 | <td class="note_box"> | |
| 33 | <img src="theme/bulb.gif"></img> <b>Lambda vs. Offline Functions</b><br><br>The best way to use the framework is to write generic off-line lazy functions (see functions) then call these functions lazily using straight-forward inline lazy-operators and lazy-statements. </td> | |
| 34 | </tr> | |
| 35 | </table> | |
| 36 | <p> | |
| 37 | While it is indeed satisfying to impress others with quite esoteric uses of operator overloading and generative programming as can be done by lazy-operators and lazy-statements, these tools are meant to be used for the right job. That said, caveat-emptor.</p> | |
| 38 | <table width="80%" border="0" align="center"> | |
| 39 | <tr> | |
| 40 | <td class="note_box"> | |
| 41 | <img src="theme/note.gif"></img> need benchmarks, benchmarks, and more benchmarks </td> | |
| 42 | </tr> | |
| 43 | </table> | |
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| 48 | <td width="20"><a href="inside_phoenix.html"><img src="theme/r_arr.gif" border="0"></a></td> | |
| 49 | </tr> | |
| 50 | </table> | |
| 51 | <br> | |
| 52 | <hr size="1"> | |
| 53 | <p class="copyright">Copyright © 2001-2002 Joel de Guzman<br> | |
| 54 | <br> | |
| 55 | <font size="2">Use, modification and distribution is subject to the Boost Software | |
| 56 | License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at | |
| 57 | http://www.boost.org/LICENSE_1_0.txt) </font> </p> | |
| 58 | </body> | |
| 59 | </html> |