* Memory:: Examining memory
* Auto Display:: Automatic display
* Print Settings:: Print settings
+* Pretty Printing:: Python pretty printing
* Value History:: Value history
* Convenience Vars:: Convenience variables
* Registers:: Registers
Show whether C@t{++} virtual function tables are pretty printed, or not.
@end table
+@node Pretty Printing
+@section Pretty Printing
+
+@value{GDBN} 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.
+
+For example, here is how a C@t{++} @code{std::string} looks without a
+pretty-printer:
+
+@smallexample
+(@value{GDBP}) 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"
+ @}
+@}
+@end smallexample
+
+With a pretty-printer for @code{std::string} only the contents are printed:
+
+@smallexample
+(@value{GDBP}) print s
+$2 = "abcd"
+@end smallexample
+
+For implementing pretty printers for new types you should read the Python API
+details (@pxref{Pretty Printing API}).
+
@node Value History
@section Value History
* Exception Handling::
* Auto-loading:: Automatically loading Python code.
* Values From Inferior::
-* Types In Python:: Python representation of types.
-* Pretty Printing:: Pretty-printing values.
+* Types In Python:: Python representation of types.
+* Pretty Printing API:: Pretty-printing values.
* Selecting Pretty-Printers:: How GDB chooses a pretty-printer.
* Commands In Python:: Implementing new commands in Python.
* Functions In Python:: Writing new convenience functions.
convenience functions.
@end table
-@node Pretty Printing
-@subsubsection Pretty Printing
-
-@value{GDBN} provides a mechanism to allow pretty-printing of values
-using Python code. The pretty-printer API allows application-specific
-code to greatly simplify the display of complex objects. This
-mechanism works for both MI and the CLI.
-
-For example, here is how a C@t{++} @code{std::string} looks without a
-pretty-printer:
+@node Pretty Printing API
+@subsubsection Pretty Printing API
-@smallexample
-(@value{GDBP}) 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"
- @}
-@}
-@end smallexample
-
-After a pretty-printer for @code{std::string} has been installed, only
-the contents are printed:
-
-@smallexample
-(@value{GDBP}) print s
-$2 = "abcd"
-@end smallexample
+An example output is provided (@pxref{Pretty Printing}).
A pretty-printer is just an object that holds a value and implements a
specific interface, defined here.
A function on one of these lists is passed a single @code{gdb.Value}
argument and should return a pretty-printer object conforming to the
-interface definition above (@pxref{Pretty Printing}). If a function
+interface definition above (@pxref{Pretty Printing API}). If a function
cannot create a pretty-printer for the value, it should return
@code{None}.
printers for the specific version of the library used by each
inferior.
-To continue the @code{std::string} example (@pxref{Pretty Printing}),
+To continue the @code{std::string} example (@pxref{Pretty Printing API}),
this code might appear in @code{gdb.libstdcxx.v6}:
@smallexample
used to look up pretty-printers. A @code{Value} is passed to each
function in order; if the function returns @code{None}, then the
search continues. Otherwise, the return value should be an object
-which is used to format the value. @xref{Pretty Printing}, for more
+which is used to format the value. @xref{Pretty Printing API}, for more
information.
@end defivar
used to look up pretty-printers. A @code{Value} is passed to each
function in order; if the function returns @code{None}, then the
search continues. Otherwise, the return value should be an object
-which is used to format the value. @xref{Pretty Printing}, for more
+which is used to format the value. @xref{Pretty Printing API}, for more
information.
@end defivar
@item displayhint
A dynamic varobj can supply a display hint to the front end. The
value comes directly from the Python pretty-printer object's
-@code{display_hint} method. @xref{Pretty Printing}.
+@code{display_hint} method. @xref{Pretty Printing API}.
@end table
Typical output will look like this:
@item displayhint
A dynamic varobj can supply a display hint to the front end. The
value comes directly from the Python pretty-printer object's
-@code{display_hint} method. @xref{Pretty Printing}.
+@code{display_hint} method. @xref{Pretty Printing API}.
@item has_more
This is an integer attribute which is nonzero if there are children
the varobj @var{name} as an argument (this is done so that the same
Python pretty-printing code can be used for both the CLI and MI).
When called, this object must return an object which conforms to the
-pretty-printing interface (@pxref{Pretty Printing}).
+pretty-printing interface (@pxref{Pretty Printing API}).
The pre-defined function @code{gdb.default_visualizer} may be used to
select a visualizer by following the built-in process
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