ceph/src/boost/libs/spirit/classic/phoenix/doc/efficiency.html

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  15       <font size="6" face="Verdana, Arial, Helvetica, sans-serif"><b>Efficiency</b></font>
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  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>
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  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>
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  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>
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  41 <img src="theme/note.gif"></img> need benchmarks, benchmarks, and more benchmarks    </td>
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  53 <p class="copyright">Copyright &copy; 2001-2002 Joel de Guzman<br>
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  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>
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