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1 files changed, 82 insertions, 64 deletions
diff --git a/docs/programmer_reference/stl_misc.html b/docs/programmer_reference/stl_misc.html index 0647d6ec..90f3d452 100644 --- a/docs/programmer_reference/stl_misc.html +++ b/docs/programmer_reference/stl_misc.html @@ -14,7 +14,7 @@ <body> <div xmlns="" class="navheader"> <div class="libver"> - <p>Library Version 11.2.5.3</p> + <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> @@ -40,12 +40,13 @@ <dl> <dt> <span class="sect2"> - <a href="stl_misc.html#idp1407848">Special notes about trivial methods</a> + <a href="stl_misc.html#idp953048">Special notes about trivial methods</a> </span> </dt> <dt> <span class="sect2"> - <a href="stl_misc.html#idp1421568">Using correct container and iterator public types</a> + <a href="stl_misc.html#idp993208">Using correct container and iterator public + types</a> </span> </dt> </dl> @@ -54,76 +55,81 @@ <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idp1407848"></a>Special notes about trivial methods</h3> + <h3 class="title"><a id="idp953048"></a>Special notes about trivial methods</h3> </div> </div> </div> - <p> - There are some standard STL methods which are meaningless in dbstl, but they are kept in - dbstl as no-ops so as to stay consistent with the standard. These are: - </p> + <p> + There are some standard STL methods which are + meaningless in dbstl, but they are kept in dbstl as no-ops + so as to stay consistent with the standard. These are: + </p> <table class="simplelist" border="0" summary="Simple list"> <tr> <td> - <code class="methodname">db_vecter::reserve();</code> + <code class="methodname">db_vecter::reserve();</code> </td> </tr> <tr> <td> - <code class="methodname">db_vector::max_size();</code> + <code class="methodname">db_vector::max_size();</code> </td> </tr> <tr> <td> - <code class="methodname">db_vector::capacity();</code> + <code class="methodname">db_vector::capacity();</code> </td> </tr> <tr> <td> - <code class="methodname">db_map::reserve();</code> + <code class="methodname">db_map::reserve();</code> </td> </tr> <tr> <td> - <code class="methodname">db_map::max_size();</code> + <code class="methodname">db_map::max_size();</code> </td> </tr> </table> <p> - <code class="methodname">db_vector<>::max_size()</code> and - <code class="methodname">db_map<>::max_size()</code> both return 2^30. This does not mean - that Berkeley DB can only hold that much data. This value is returned to conform to some - compilers' overflow rules — if we set bigger numbers like 2^32 or 2^31, some compilers - complain that the number has overflowed. - </p> - <p> - See the Berkeley DB documentation for information about limitations on how much data a - database can store. - </p> + <code class="methodname">db_vector<>::max_size()</code> and + <code class="methodname">db_map<>::max_size()</code> + both return 2^30. This does not mean that Berkeley DB can + only hold that much data. This value is returned to + conform to some compilers' overflow rules — if we + set bigger numbers like 2^32 or 2^31, some compilers + complain that the number has overflowed. + </p> + <p> + See the Berkeley DB documentation for information about + limitations on how much data a database can store. + </p> <p> - There are also some read-only functions. You set the configuration - for these using the Berkeley DB API. You access them using the container's methods. Again, - this is to keep consistent with C++ standard STL containers, such as: - </p> + There are also some read-only functions. You set the + configuration for these using the Berkeley DB API. You + access them using the container's methods. Again, this is + to keep consistent with C++ standard STL containers, such + as: + </p> <table class="simplelist" border="0" summary="Simple list"> <tr> <td> - <code class="methodname">db_map::key_comp();</code> + <code class="methodname">db_map::key_comp();</code> </td> </tr> <tr> <td> - <code class="methodname">db_map::value_comp();</code> + <code class="methodname">db_map::value_comp();</code> </td> </tr> <tr> <td> - <code class="methodname">db_map::hash_funct();</code> + <code class="methodname">db_map::hash_funct();</code> </td> </tr> <tr> <td> - <code class="methodname">db_map::key_eq();</code> + <code class="methodname">db_map::key_eq();</code> </td> </tr> </table> @@ -132,48 +138,60 @@ <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idp1421568"></a>Using correct container and iterator public types</h3> + <h3 class="title"><a id="idp993208"></a>Using correct container and iterator public + types</h3> </div> </div> </div> + <p> + All public types defined by the C++ STL specification + are present in dbstl. One thing to note is the <span class="bold"><strong>value_type</strong></span>. dbstl defines the + <span class="bold"><strong>value_type</strong></span> for each + iterator and container class to be the raw type without + the + <code class="classname">ElementRef</code>/<code class="classname">ElementHolder</code> + wrapper, so this type of variable can not be used to store + data in a database. There is a <span class="bold"><strong>value_type_wrap</strong></span> + type for each container + and iterator type, with the raw type wrapped by the + <code class="classname">ElementRef</code>/<code class="classname">ElementHolder</code>. + </p> <p> - All public types defined by the C++ STL specification are present in dbstl. One thing to - note is the <span class="bold"><strong>value_type</strong></span>. dbstl defines the <span class="bold"><strong>value_type</strong></span> for each iterator and container class to be the raw - type without the <code class="classname">ElementRef</code>/<code class="classname">ElementHolder</code> - wrapper, so this type of variable can not be used to store data in a database. There is a - <span class="bold"><strong>value_type_wrap</strong></span> type for each container and iterator type, - with the raw type wrapped by the - <code class="classname">ElementRef</code>/<code class="classname">ElementHolder</code>. - </p> - <p> - For example, when type <code class="literal">int_vector_t</code> is defined as - </p> + For example, when type <code class="literal">int_vector_t</code> + is defined as + </p> <pre class="programlisting">db_vector<int, ElementHolder<int> ></pre> <p> - its <span class="bold"><strong>value_type</strong></span> is <code class="literal">int</code>, its - <span class="bold"><strong>value_type_wrap</strong></span> is <code class="literal">ElementHolder<int></code>, - and its reference and pointer types are <code class="literal">ElementHolder<int>&</code> and - <code class="literal">ElementHolder<int>*</code> respectively. If you need to store data, use - <span class="bold"><strong>value_type_wrap</strong></span> to make use of the wrapper to store data - into database. - </p> - <p> - The reason we leave <span class="bold"><strong>value_type</strong></span> as the raw type is that we - want the existing algorithms in the STL library to work with dbstl because we have seen that - without doing so, a few tests will fail. - </p> - <p> - You need to use the same type as the return type of the data element retrieval functions to - hold a value in order to properly manipulate the data element. For example, when calling - </p> + its <span class="bold"><strong>value_type</strong></span> is + <code class="literal">int</code>, its <span class="bold"><strong>value_type_wrap</strong></span> + is <code class="literal">ElementHolder<int></code>, and its + reference and pointer types are + <code class="literal">ElementHolder<int>&</code> and + <code class="literal">ElementHolder<int>*</code> + respectively. If you need to store data, use <span class="bold"><strong>value_type_wrap</strong></span> to make use of + the wrapper to store data into database. + </p> + <p> + The reason we leave <span class="bold"><strong>value_type</strong></span> + as the raw type is that we want the existing algorithms in the STL + library to work with dbstl because we have seen that without doing so, + a few tests will fail. + </p> + <p> + You need to use the same type as the return type of the + data element retrieval functions to hold a value in order + to properly manipulate the data element. For example, when + calling + </p> <pre class="programlisting">db_vector<T>::operator[]</pre> <p> - check that the return type for this function is - </p> + check that the return type for this function is + </p> <pre class="programlisting">db_vector<T>::datatype_wrap</pre> - <p> - Then, hold the return value using an object of the same type: - </p> + <p> + Then, hold the return value using an object of the same + type: + </p> <pre class="programlisting">db_vector<T>::datatype_wrap refelem = vctr[3];</pre> </div> </div> |