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| <h3 class="section">10.9 Pretty Printing</h3> |
| |
| <p><span class="sc">gdb</span> provides a mechanism to allow pretty-printing of values using |
| Python code. It greatly simplifies the display of complex objects. This |
| mechanism works for both MI and the CLI. |
| |
| <p>For example, here is how a C<tt>++</tt> <code>std::string</code> looks without a |
| pretty-printer: |
| |
| <pre class="smallexample"> (gdb) print s |
| $1 = { |
| static npos = 4294967295, |
| _M_dataplus = { |
| <std::allocator<char>> = { |
| <__gnu_cxx::new_allocator<char>> = { |
| <No data fields>}, <No data fields> |
| }, |
| members of std::basic_string<char, std::char_traits<char>, |
| std::allocator<char> >::_Alloc_hider: |
| _M_p = 0x804a014 "abcd" |
| } |
| } |
| </pre> |
| <p>With a pretty-printer for <code>std::string</code> only the contents are printed: |
| |
| <pre class="smallexample"> (gdb) print s |
| $2 = "abcd" |
| </pre> |
| <p>For implementing pretty printers for new types you should read the Python API |
| details (see <a href="Pretty-Printing-API.html#Pretty-Printing-API">Pretty Printing API</a>). |
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