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20      <h1 align="left">Boost Library Requirements and Guidelines</h1>
21      <p align="left"><a href="#Introduction">Introduction</a><br>
22         <a href="#Requirements">Requirements</a><br>
23         &nbsp;&nbsp;&nbsp; <a href="#License">License requirements</a><br>
24         &nbsp;&nbsp;&nbsp; <a href="#Portability">Portability requirements</a><br>
25         &nbsp;&nbsp;&nbsp; <a href="#Ownership">Ownership</a><br>
26         <a href="#Guidelines">Guidelines</a><br>
27         &nbsp;&nbsp;&nbsp; <a href="#Design_and_Programming">Design and programming</a><br>
28         &nbsp;&nbsp;&nbsp; <a href="#Directory_structure">Directory structure and
29            filenames</a><br>
30         &nbsp;&nbsp;&nbsp; <a href="#Naming&shy;_consistency">Naming consistency</a><br>
31         &nbsp;&nbsp;&nbsp; <a href="#Documentation">Documentation</a><br>
32         <a href="#Rationale">Rationale</a><br>
33         &nbsp;&nbsp;&nbsp; <a href="#Exception-specification">Exception-specification
34            rationale</a><br>
35         &nbsp;&nbsp;&nbsp; <a href="#Naming">Naming conventions rationale</a><br>
36         &nbsp;&nbsp;&nbsp; <a href="#code_fonts">Source code fonts rationale</a><br>
37         &nbsp;&nbsp;&nbsp; <a href="#Tabs">Tabs rationale</a><br>
38         &nbsp;&nbsp;&nbsp; <a href="#JavaScript">ECMAScript/JavaScript rationale</a><br>
39         &nbsp;&nbsp;&nbsp; <a href="#Rationale_rationale">Rationale rationale</a><br>
40         &nbsp;&nbsp;&nbsp; <a href="#Acknowledgements">Acknowledgements rationale</a></p>
41      <h2 align="left"><a name="Introduction">Introduction</a></h2>
42      <p align="left">This page describes requirements and guidelines for the content of
43         a library submitted to Boost.</p>
44      <p align="left">See the <a href="submission_process.htm">Boost Library Submission
45            Process</a> page for a description of the process involved.</p>
46      <h2 align="left"><a name="Requirements">Requirements</a></h2>
47      <p>To avoid the frustration and wasted time of a proposed library being rejected,
48         it must meets these requirements:</p>
49      <ul>
50         <li>
51            The license must meet the <a href="#License">license requirements</a>
52         below. Restricted licenses like the GPL and LGPL are not acceptable.
53         <li>
54            The copyright <a href="#Ownership">ownership</a>
55         must be clear.
56         <li>
57         The library must be generally useful and not restricted to a narrow problem
58         domain.
59         <li>
60            The library must meet the <a href="#Portability">portability requirements</a>
61         below.&nbsp;
62         <li>
63            The library must come reasonably close to meeting the <a href="#Guidelines">Guidelines</a>
64            below.
65            <ul>
66               <li>
67                  <a href="#Design_and_Programming">Design and Programming</a>
68               <li>
69                  <a href="#Directory_structure">Directory Structure</a>
70               <li>
71                  <a href="#Documentation">Documentation</a></li>
72            </ul>
73         <li>
74            The author must be willing to participate in discussions on the mailing list,
75            and to refine the library accordingly.</li>
76      </ul>
77      <p>There's no requirement that an author read the mailing list for a time before
78         making a submission. It has been noted, however, that submissions which begin
79         "I just started to read this mailing list ..." seem to fail, often
80         embarrassingly.</p>
81      <h3 align="left"><a name="License">License</a> requirements</h3>
82      <p>The preferred way to meet the license requirements is to use the <a href="../LICENSE_1_0.txt">
83            Boost Software License</a>. See <a href="license_info.html">license information</a>.
84         If for any reason you do not intend to use the Boost Software License, please
85         discuss the issues on the Boost <a href="mailing_lists.htm#main">developers
86            mailing list</a> first.</p>
87      <p>The license requirements:</p>
88      <ul>
89         <li>
90         Must be simple to read and understand.
91         <li>
92         Must grant permission without fee to copy, use and modify the software for any
93         use (commercial and non-commercial).
94         <li>
95         Must require that the license appear on all copies of the software source code.
96         <li>
97         Must not require that the license appear with executables or other binary uses
98         of the library.
99         <li>
100         Must not require that the source code be available for execution or other
101         binary uses of the library.
102         <li>
103            May restrict the use of the name and description of the library to the standard
104            version found on the Boost web site.</li>
105      </ul>
106      <h3 align="left"><a name="Portability">Portability</a> requirements</h3>
107      <ul>
108         <li>
109            <p align="left">A library's interface must portable and not restricted to a
110               particular compiler or operating system.</p>
111         <li>
112            <p align="left">A library's implementation must if possible be portable and not
113               restricted to a particular compiler or operating system.&nbsp; If a portable
114               implementation is not possible, non-portable constructions are acceptable if
115               reasonably easy to port to other environments, and implementations are provided
116               for at least two popular operating systems (such as UNIX and Windows).</p>
117         <li>
118            <p align="left">There is no requirement that a library run on C++ compilers which
119               do not conform to the ISO standard.&nbsp;</p>
120         <li>
121            <p align="left">There is no requirement that a library run on any particular C++
122               compiler.&nbsp; Boost contributors often try to ensure their libraries work
123               with popular compilers.&nbsp; The boost/config.hpp <a href="../libs/config/config.htm">
124                  configuration header</a> is the preferred mechanism for working around
125               compiler deficiencies.</p>
126         </li>
127      </ul>
128      <p align="left">Since there is no absolute way to prove portability, many boost
129         submissions demonstrate practical portability by compiling and executing
130         correctly with two different C++ compilers, often under different operating
131         systems.&nbsp; Otherwise reviewers may disbelieve that porting is in fact
132         practical.</p>
133      <h3 align="left"><a name="Ownership">Ownership</a></h3>
134      <p align="left">Are you sure you own the library you are thinking of
135         submitting?&nbsp;&nbsp; "How to Copyright Software" by MJ Salone, Nolo Press,
136         1990 says:</p>
137      <blockquote>
138         <p align="left">Doing work on your own time that is very similar to programming
139            you do for your employer on company time can raise nasty legal problems.&nbsp; 
140            In this situation, it's best to get a written release from your employer in
141            advance.</p>
142      </blockquote>
143      <p align="left">Place a copyright notice in all the important files you submit.
144         Boost won't accept libraries without clear copyright information.</p>
145      <h2 align="left"><a name="Guidelines">Guidelines</a></h2>
146      <p align="left">Please use these guidelines as a checklist for preparing the
147         content a library submission.&nbsp; Not every guideline applies to every
148         library, but a reasonable effort to comply is expected.</p>
149      <h3><a name="Design_and_Programming">Design and Programming</a></h3>
150      <ul>
151         <li>
152            Aim first for clarity and correctness; optimization should be only a secondary
153            concern in most Boost libraries.</li>
154      </ul>
155      <ul>
156         <li>
157            Aim for ISO Standard C++. Than means making effective use of the standard
158            features of the language, and avoiding non-standard compiler extensions. It
159            also means using the C++ Standard Library where applicable.</li>
160      </ul>
161      <ul>
162         <li>
163            Headers should be good neighbors. See the <a href="header.htm">header policy</a>.
164            See <a href="#Naming&shy;_consistency">Naming consistency</a>.</li>
165      </ul>
166      <ul>
167         <li>
168            Follow quality programming practices. See, for example, "Effective C++" 2nd
169            Edition, and "More Effective C++", both by Scott Meyers, published by Addison
170            Wesley.</li>
171      </ul>
172      <ul>
173         <li>
174            Use the C++ Standard Library or other Boost libraries, but only when the
175            benefits outweigh the costs.&nbsp; Do not use libraries other than the C++
176            Standard Library or Boost. See <a href="library_reuse.htm">Library reuse</a>.</li>
177      </ul>
178      <ul>
179         <li>
180            Read <a href="imp_vars.htm">Implementation Variation</a> to see how to supply
181            performance, platform, or other implementation variations.</li>
182      </ul>
183      <ul>
184         <li>
185            Read the <A href="separate_compilation.html">guidelines for libraries with
186               separate source</A>
187         to see how to ensure that compiled link libraries meet user expectations.
188         </li>
189      </ul>
190      <ul>
191         <LI>
192            Use the naming conventions of the C++ Standard Library (See <a href="#Naming">Naming
193               conventions rationale</a>):
194            <br>
195            &nbsp;<ul>
196               <li>
197               Names (except as noted below) should be all lowercase, with words separated by
198               underscores.
199               <li>
200                  Acronyms should be treated as ordinary names (e.g. <code>xml_parser</code> instead
201                  of <code>XML_parser</code>).
202               <li>
203               Template parameter names begin with an uppercase letter.
204               <li>
205                  Macro (gasp!) names all uppercase and begin with BOOST_.</li>
206            </ul>
207         </LI>
208      </ul>
209      <ul>
210         <li>
211            Choose meaningful names - explicit is better than implicit, and readability
212            counts. There is a strong preference for clear and descriptive names, even if
213            lengthy.</li>
214      </ul>
215      <ul>
216         <li>
217            Use exceptions to report errors where appropriate, and write code that is safe
218            in the face of exceptions.</li>
219      </ul>
220      <ul>
221         <li>
222            Avoid exception-specifications. See <a href="#Exception-specification">exception-specification
223               rationale</a>.</li>
224      </ul>
225      <ul>
226         <li>
227            Provide sample programs or confidence tests so potential users can see how to
228            use your library.</li>
229      </ul>
230      <ul>
231         <li>
232            Provide a regression test program or programs which follow the <a href="test_policy.htm">
233               Test Policies and Protocols</a>.</li>
234      </ul>
235      <ul>
236         <li>
237            Although some boost members use proportional fonts, tabs, and unrestricted line
238            lengths in their own code, boost's widely distributed source code should follow
239            more conservative guidelines:
240            <ul>
241               <li>
242                  Use fixed-width fonts.&nbsp; See <a href="#code_fonts">fonts rationale</a>.
243               <li>
244                  Use spaces rather than tabs. See <a href="#Tabs">tabs rationale</a>.
245               <li>
246                  Limit line lengths to 80 characters.</li>
247            </ul>
248         </li>
249      </ul>
250      <ul>
251         <li>
252            End all documentation files (HTML or otherwise) with a copyright message and a
253            licensing message. See the <a href="#Copyright">end of this file</a> for an
254            example of the preferred form.</li>
255      </ul>
256      <ul>
257         <li>
258            Begin all source files (including programs, headers, scripts, etc.) with:
259            <br>
260            &nbsp;<ul>
261               <li>
262                  A comment line describing the contents of the file.<br>
263               &nbsp;
264               <li>
265                  Comments describing copyright and licensing. The preferred form is:<br>
266                  <br>
267                  <code>//&nbsp; Copyright Jane Programmer 2002. Use, modification, and distribution
268                     are<br>
269                     //&nbsp; subject to the Boost Software License, Version 1.0. (See accompanying<br>
270                     //&nbsp; file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)<br>
271                  </code>
272                  <br>
273                  Please leave an empty line before and after the copyright and license comments.
274                  It is fine if the copyright and license messages are on different lines, but
275                  there should be no other intervening text. Do not include "All rights reserved"
276                  in the copyright message.<br>
277                  <br>
278                  See <a href="license_info.html">license information page</a> for more
279                  information about the Boost Software License.<br>
280                  <br>
281                  Note that developers should not include a copy of <code>LICENSE_1_0.txt</code> in
282                  their libraries; Boost distributions already include a copy in the Boost root
283                  directory.<br>
284               &nbsp;
285               <li>
286                  A comment line referencing your library on the Boost web site. For example:<br>
287                  <br>
288                  <code>//&nbsp; See http://www.boost.org/libs/foo for library home page.</code><br>
289                  <br>
290                  where <code>foo</code> is the directory name (see below) for your library. As
291                  well as aiding users who come across a Boost file detached from its
292                  documentation, some of Boost's automatic tools depend on this comment to
293                  identify which library header files belong to.</li>
294            </ul>
295         </li>
296      </ul>
297      <ul>
298         <li>
299            Make sure your code compiles in the presence of the <code>min()</code> and <code>max()</code>
300            macros. Some platform headers define <code>min()</code> and <code>max()</code> macros which
301            cause some common C++ constructs to fail to compile. Some simple tricks can protect your code
302            from inappropriate macro substitution:<br>&nbsp;
303            <ul>
304               <li>
305                  If you want to call <code>std::min()</code> or <code>std::max()</code>:<br>&nbsp;
306                  <ul>
307                     <li>
308                        If you do not require argument-dependent look-up, use <code>(std::min)(a,b)</code>.
309                     </li>&nbsp;
310                     <li>
311                        If you do require argument-dependent look-up, you should:<br>&nbsp;
312                        <ul>
313                           <li><code>#include &lt;boost/config.hpp&gt;</code></li>&nbsp;
314                           <li>Use <code>BOOST_USING_STD_MIN();</code> to bring <code>std::min()</code> into
315                               the current scope.</li>&nbsp;
316                           <li>Use <code>min BOOST_PREVENT_MACRO_SUBSTITUTION (a,b);</code> to make an
317                               argument-dependent call to <code>min(a,b)</code>.</li>&nbsp;
318                        </ul>
319                     </li>
320                  </ul>&nbsp;
321               </li>
322               <li>
323                  If you want to call <code>std::numeric_limits&lt;int&gt;::max()</code>, use
324                  <code>(std::numeric_limits&lt;int&gt;::max)()</code> instead.<br>&nbsp;
325               </li>
326               <li>
327                  If you want to call a <code>min()</code> or <code>max()</code> member function,
328                  instead to doing <code>obj.min()</code>, use <code>(obj.min)()</code>.<br>&nbsp;
329               </li>
330               <li>
331                  If you want to declare or define a function or a member function named <code>min</code>
332                  or <code>max</code>, then you must use the <code>BOOST_PREVENT_MACRO_SUBSTITUTION</code>
333                  macro. Instead of writing <code>int min() { return 0; }</code> you should write
334                  <code>int min BOOST_PREVENT_MACRO_SUBSTITUTION () { return 0; }</code> This is true
335                  regardless if the function is a free (namespace scope) function, a member function or a
336                  static member function, and it applies for the function declaration as well as the
337                  function definition.<br>&nbsp;
338               </li>
339            </ul>
340         </li>
341      </ul>
342      <h3><a name="Directory_structure">Directory Structure</a> and Filenames</h3>
343      <ul>
344         <li>
345         File and directory names must contain only <b>lowercase</b> ASCII letters , numbers,
346         underscores, and a period.&nbsp; Leading character must be alphabetic. Maximum
347         length 31. Only a single period is permitted.&nbsp; These requirements ensure
348         file and directory names are relatively portable.
349         <li>
350            Files intended to be processed by a C++ compiler as part
351            of a translation unit should have <b>a three-letter
352            extension ending in &quot;pp&quot;</b>.  Other files should
353            <i>not</i> use extensions ending in &quot;pp&quot;.  This
354            convention makes it easy to identify all of the C++ source
355            in Boost.</li>
356         <li>
357            All libraries have at their highest level a primary directory named for the
358            particular library. See <a href="#Naming&shy;_consistency">Naming consistency</a>.
359         The primary directory may have sub-directories.
360         <li>
361            For very simple libraries implemented entirely within the library header, all
362            files go in the primary directory (except headers, which go in the boost header
363            directory).</li>
364      </ul>
365      <blockquote>
366         <p><b>Boost standard sub-directory names</b></p>
367         <table border="1" cellpadding="5">
368            <tr>
369               <td><b>Sub-directory</b></td>
370               <td><b>Contents</b></td>
371               <td><b>Required</b></td>
372            </tr>
373            <tr>
374               <td><code>build</code></td>
375               <td>Library build files such as a Jamfile.</td>
376               <td>If any build files.</td>
377            </tr>
378            <tr>
379               <td><code>doc</code></td>
380               <td>Documentation (HTML) files.</td>
381               <td>If several doc files.</td>
382            </tr>
383            <tr>
384               <td><code>example</code></td>
385               <td>Sample program files.</td>
386               <td>If several sample files.</td>
387            </tr>
388            <tr>
389               <td><code>src</code></td>
390               <td>Source files which must be compiled to build the library.&nbsp;</td>
391               <td>If any source files.</td>
392            </tr>
393            <tr>
394               <td><code>test</code></td>
395               <td>Regression or other test programs or scripts.</td>
396               <td>If several test files.</td>
397            </tr>
398         </table>
399      </blockquote>
400      <h4><a name="Redirection">Redirection</a></h4>
401      <p>The primary directory should always contain a file named index.html (or
402         index.htm). Authors have requested this so that they can publish URL's in the
403         form <i>http://www.boost.org/libs/lib-name</i> with the assurance a
404         documentation reorganization won't invalidate the URL. Boost's internal tools
405         are also simplified by knowing that a library's documentation is always
406         reachable via the simplified URL.</p>
407      <p>If the documentation is in a doc sub-directory, the primary directory
408         index.html file should just do an automatic redirection to the doc
409         subdirectory:</p>
410      <blockquote>
411         <pre>&lt;html&gt;
412&lt;head&gt;
413&lt;meta http-equiv="refresh" content="0; URL=doc/index.html"&gt;
414&lt;/head&gt;
415&lt;body&gt;
416Automatic redirection failed, please go to
417&lt;a href="doc/index.html"&gt;doc/index.html&lt;/a&gt;
418&lt;/body&gt;
419&lt;/html&gt;</pre>
420      </blockquote>
421      <h3><a name="Naming&shy;_consistency">Naming consistency</a></h3>
422      <p>As library developers and users have gained experience with Boost, the
423         following consistent naming approach has come to be viewed as very helpful,
424         particularly for larger libraries that need their own header subdirectories
425         and namespaces.</p>
426      <p>Here is how it works. The library is given a name that describes the contents
427         of the library. Cryptic abbreviations are strongly discouraged. Following the
428         practice of the C++ Standard Library, names are usually singular rather than
429         plural. For example, a library dealing with file systems might chose the
430         name "filesystem", but not "filesystems", "fs" or "nicecode".</p>
431      <ul>
432         <li>
433            The library's primary directory (in parent <i>boost-root/libs</i>) is given
434            that same name.&nbsp; For example, <i>boost-root/libs/filesystem</i>.<br>
435         &nbsp;
436         <li>
437            The library's primary header directory (in parent <i>boost-root/boost</i>) is
438            given that same name. For example, <i>boost-root/boost/filesystem</i>.<br>
439         &nbsp;
440         <li>
441            The library's primary namespace (in parent <i>::boost</i>) is given that same
442            name, except when there's a component with that name (e.g., <i>boost::tuple</i>), in which case the namespace name is pluralized. For example, <i>::boost::filesystem</i>.</li>
443      </ul>
444
445    <p>When documenting Boost libraries, follow these conventions (see also the following section of this document):
446    <ul>
447      <li>The library name is set in roman type.</li>
448      <li>The library name is capitalized.</li>
449      <li>A period between "Boost" and the library name (e.g., Boost.Bind) is used if and only if the library name is not followed by the word "library".</li>
450      <li>The word "library" is not part of the library name and is therefore lowercased.</li>
451    </ul>
452    <p>Here are a few examples of how to apply these conventions:
453    <ul>
454      <li>Boost.Bind was written by Peter Dimov.</li>
455      <li>The Boost Bind library was written by Peter Dimov.</li>
456      <li>I regularly use Bind, a Boost library written by Peter Dimov.</li>
457    </ul>
458
459      <h3><a name="Documentation">Documentation</a></h3>
460      <p>Even the simplest library needs some documentation; the amount should be
461         proportional to the need.&nbsp; The documentation should assume the readers
462         have a basic knowledge of C++, but are not necessarily experts.</p>
463      <p>The format for documentation should be HTML, and should not require an advanced
464         browser or server-side extensions. Style sheets are acceptable.
465         ECMAScript/JavaScript is not acceptable. The documentation entry point should
466         always be a file named index.html or index.htm; see <a href="#Redirection">Redirection</a>.</p>
467      <p>There is no single right way to do documentation. HTML documentation is often
468         organized quite differently from traditional printed documents. Task-oriented
469         styles differ from reference oriented styles. In the end, it comes down to the
470         question: Is the documentation sufficient for the mythical "average" C++
471         programmer to use the library successfully?</p>
472      <p>Appropriate topics for documentation often include:
473         <ul>
474            <li>
475            General introduction to the library.
476            <li>
477            Description of each class.
478            <li>
479            Relationship between classes.
480            <li>
481            For each function, as applicable, description, requirements (preconditions),
482            effects, post-conditions, returns, and throws.
483            <li>
484            Discussion of error detection and recovery strategy.
485            <li>
486            How to use including description of typical uses.
487            <li>
488            How to compile and link.
489            <li>
490            How to test.
491            <li>
492            Version or revision history.
493            <li>
494               Rationale for design decisions.&nbsp; See <a href="#Rationale">Rationale rationale</a>.
495            <li>
496               Acknowledgements.&nbsp; See <a href="#Acknowledgements">Acknowledgments rationale.</a></li>
497         </ul>
498      <p>If you need more help with how to write documentation you can check out the
499         article on <a href="writingdoc/index.html">Writing Documentation for Boost</a>.</p>
500      <h2><a name="Rationale">Rationale</a></h2>
501      <p>Rationale for some of the requirements and guidelines follows.</p>
502      <hr>
503      <h3><a name="Exception-specification">Exception-specification</a> rationale</h3>
504      <p>Exception specifications [ISO 15.4] are sometimes coded to indicate what
505         exceptions may be thrown, or because the programmer hopes they will improved
506         performance.&nbsp; But consider the following member from a smart pointer:</p>
507      <pre>    T&amp; operator*() const throw()  { return *ptr; }</pre>
508      <p>This function calls no other functions; it only manipulates fundamental data
509         types like pointers Therefore, no runtime behavior of the
510         exception-specification can ever be invoked.&nbsp; The function is completely
511         exposed to the compiler; indeed it is declared inline Therefore, a smart
512         compiler can easily deduce that the functions are incapable of throwing
513         exceptions, and make the same optimizations it would have made based on the
514         empty exception-specification. A "dumb" compiler, however, may make all kinds
515         of pessimizations.</p>
516      <p>For example, some compilers turn off inlining if there is an
517         exception-specification.&nbsp; Some compilers add try/catch blocks. Such
518         pessimizations can be a performance disaster which makes the code unusable in
519         practical applications.</p>
520      <p>Although initially appealing, an exception-specification tends to have
521         consequences that require <b>very</b> careful thought to understand. The
522         biggest problem with exception-specifications is that programmers use them as
523         though they have the effect the programmer would like, instead of the effect
524         they actually have.</p>
525      <p>A non-inline function is the one place a "throws nothing"
526         exception-specification may have some benefit with some compilers.</p>
527      <hr>
528      <h3><a name="Naming">Naming</a> conventions rationale</h3>
529      <p>The C++ standard committee's Library Working Group discussed this issue in
530         detail, and over a long period of time. The discussion was repeated again in
531         early boost postings. A short summary:</p>
532      <ul>
533         <li>
534         Naming conventions are contentious, and although several are widely used, no
535         one style predominates.
536         <li>
537         Given the intent to propose portions of boost for the next revision of the C++
538         standard library, boost decided to follow the standard library's conventions.
539         <li>
540            Once a library settles on a particular convention, a vast majority of
541            stakeholders want that style to be consistently used.
542         </li>
543      </ul>
544      <hr>
545      <h3>Source <a name="code_fonts">code fonts</a> rationale</h3>
546      <p>Dave Abrahams comments: An important purpose (I daresay the primary purpose) of
547         source code is communication: the documentation of intent. This is a doubly
548         important goal for boost, I think. Using a fixed-width font allows us to
549         communicate with more people, in more ways (diagrams are possible) right there
550         in the source. Code written for fixed-width fonts using spaces will read
551         reasonably well when viewed with a variable-width font, and as far as I can
552         tell every editor supporting variable-width fonts also supports fixed width. I
553         don't think the converse is true.</p>
554      <hr>
555      <h3><a name="Tabs">Tabs</a> rationale</h3>
556      <p>Tabs are banned because of the practical problems caused by tabs in
557         multi-developer projects like Boost, rather than any dislike in principle. See <a href="mailing_lists.htm#archive">
558            mailing list archives</a>. Problems include maintenance of a single source
559         file by programmers using tabs and programmers using spaces, and the difficulty
560         of enforcing a consistent tab policy other than just "no tabs". Discussions
561         concluded that Boost files should either all use tabs, or all use spaces, and
562         thus the decision to stick with spaces.</p>
563      <hr>
564      <h3>ECMAScript/<a name="JavaScript">JavaScript</a> rationale</h3>
565      <p>Before the 1.29.0 release, two Boost libraries added ECMAScript/JavaScript
566         documentation. Controversy followed (see <a href="mailing_lists.htm#archive">mailing
567            list archives</a>), and the developers were asked to remove the
568         ECMAScript/JavaScript. Reasons given for banning included:</p>
569      <ul>
570         <li>
571         Incompatible with some older browsers and some text based browsers.
572         <li>
573         Makes printing docs pages difficult.
574         <li>
575         Often results in really bad user interface design.
576         <li>
577         "It's just annoying in general."
578         <li>
579         Would require Boost to test web pages for ECMAScript/JavaScript compliance.
580         <li>
581            Makes docs maintenance by other than the original developer more difficult.</li>
582      </ul>
583      <hr>
584      <h3><a name="Rationale_rationale">Rationale rationale</a></h3>
585      <p>Rationale is defined as "The fundamental reasons for something; basis" by the
586         American Heritage Dictionary.</p>
587      <p>Beman Dawes comments:&nbsp; Failure to supply contemporaneous rationale for
588         design decisions is a major defect in many software projects. Lack of accurate
589         rationale causes issues to be revisited endlessly, causes maintenance bugs when
590         a maintainer changes something without realizing it was done a certain way for
591         some purpose, and shortens the useful lifetime of software.</p>
592      <p>Rationale is fairly easy to provide at the time decisions are made, but very
593         hard to accurately recover even a short time later.</p>
594      <hr>
595      <h3><a name="Acknowledgements">Acknowledgements</a> rationale</h3>
596      <p>As a library matures, it almost always accumulates improvements suggested to
597         the authors by other boost members.&nbsp; It is a part of the culture of
598         boost.org to acknowledge such contributions, identifying the person making the
599         suggestion.&nbsp; Major contributions are usually acknowledged in the
600         documentation, while minor fixes are often mentioned in comments within the
601         code itself.</p>
602      <hr>
603      <p>Revised
604         <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan --> 
605         04 November, 2003<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
606      <p>
607         © <a name="Copyright">Copyright</a> Beman Dawes 2003.</p>
608    <p> Distributed under the Boost Software License, Version 1.0.
609    (See accompanying file <a href="../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
610    copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)
611    </p>
612   </body>
613</html>
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