Execute the?statement?(given as a string) under debugger control. The debugger prompt appears before any code is executed; you can set breakpoints and type?continue, or you can step through the statement using?step?or?next?(all these commands are explained below). The optional?globals?and?locals?arguments specify the environment in which the code is executed; by default the dictionary of the module?__main__?is used. (See the explanation of the?exec?statement or the?eval()?built-in function.)

Evaluate the?expression?(given as a string) under debugger control. When?runeval()?returns, it returns the value of the expression. Otherwise this function is similar to?run().

Call the?function?(a function or method object, not a string) with the given arguments. When?runcall()?returns, it returns whatever the function call returned. The debugger prompt appears as soon as the function is entered.

Enter the debugger at the calling stack frame. This is useful to hard-code a breakpoint at a given point in a program, even if the code is not otherwise being debugged (e.g. when an assertion fails).

Enter post-mortem debugging of the given?traceback?object. If no?traceback?is given, it uses the one of the exception that is currently being handled (an exception must be being handled if the default is to be used).

Enter post-mortem debugging of the traceback found in?sys.last_traceback.

Pdb?is the debugger class.

The?completekey,?stdin?and?stdout?arguments are passed to the underlying?cmd.Cmd?class; see the description there.

The?skip?argument, if given, must be an iterable of glob-style module name patterns. The debugger will not step into frames that originate in a module that matches one of these patterns.?[1]

Example call to enable tracing with?skip:

New in version 2.7:?The?skip?argument.

See the documentation for the functions explained above.

With a?lineno?argument, set a break there in the current file. With a?function?argument, set a break at the first executable statement within that function. The line number may be prefixed with a filename and a colon, to specify a breakpoint in another file (probably one that hasn’t been loaded yet). The file is searched on?sys.path. Note that each breakpoint is assigned a number to which all the other breakpoint commands refer.

If a second argument is present, it is an expression which must evaluate to true before the breakpoint is honored.

Without argument, list all breaks, including for each breakpoint, the number of times that breakpoint has been hit, the current ignore count, and the associated condition if any.

Specify a list of commands for breakpoint number?bpnumber. The commands themselves appear on the following lines. Type a line containing just ‘end’ to terminate the commands. An example:

To remove all commands from a breakpoint, type commands and follow it immediately with end; that is, give no commands.

With no?bpnumber?argument, commands refers to the last breakpoint set.

You can use breakpoint commands to start your program up again. Simply use the continue command, or step, or any other command that resumes execution.

Specifying any command resuming execution (currently continue, step, next, return, jump, quit and their abbreviations) terminates the command list (as if that command was immediately followed by end). This is because any time you resume execution (even with a simple next or step), you may encounter another breakpoint–which could have its own command list, leading to ambiguities about which list to execute.

If you use the ‘silent’ command in the command list, the usual message about stopping at a breakpoint is not printed. This may be desirable for breakpoints that are to print a specific message and then continue. If none of the other commands print anything, you see no sign that the breakpoint was reached.

New in version 2.5.

Continue execution until the line with the line number greater than the current one is reached or when returning from current frame.

New in version 2.6.

Set the next line that will be executed. Only available in the bottom-most frame. This lets you jump back and execute code again, or jump forward to skip code that you don’t want to run.

It should be noted that not all jumps are allowed — for instance it is not possible to jump into the middle of a?for?loop or out of a?finally?clause.

Evaluate the?expression?in the current context and print its value.

Note

print?can also be used, but is not a debugger command — this executes the Python?print?statement.

Creates an alias called?name?that executes?command. The command must?not?be enclosed in quotes. Replaceable parameters can be indicated by?%1,?%2, and so on, while?%*?is replaced by all the parameters. If no command is given, the current alias for?name?is shown. If no arguments are given, all aliases are listed.

Aliases may be nested and can contain anything that can be legally typed at the pdb prompt. Note that internal pdb commands?can?be overridden by aliases. Such a command is then hidden until the alias is removed. Aliasing is recursively applied to the first word of the command line; all other words in the line are left alone.

As an example, here are two useful aliases (especially when placed in the?.pdbrc?file):

Execute the (one-line)?statement?in the context of the current stack frame. The exclamation point can be omitted unless the first word of the statement resembles a debugger command. To set a global variable, you can prefix the assignment command with a?globalcommand on the same line, e.g.:

Restart the debugged Python program. If an argument is supplied, it is split with “shlex” and the result is used as the new sys.argv. History, breakpoints, actions and debugger options are preserved. “restart” is an alias for “run”.

New in version 2.6.