path: root/devdocs/python~3.12/library%2Fbdb.html

 <span id="bdb-debugger-framework"></span><h1>bdb — Debugger framework</h1> <p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.12/Lib/bdb.py">Lib/bdb.py</a></p>  <p>The <a class="reference internal" href="#module-bdb" title="bdb: Debugger framework."><code>bdb</code></a> module handles basic debugger functions, like setting breakpoints or managing execution via the debugger.</p> <p>The following exception is defined:</p> <dl class="py exception"> <dt class="sig sig-object py" id="bdb.BdbQuit">
<code>exception bdb.BdbQuit</code> </dt> <dd>
<p>Exception raised by the <a class="reference internal" href="#bdb.Bdb" title="bdb.Bdb"><code>Bdb</code></a> class for quitting the debugger.</p> </dd>
</dl> <p>The <a class="reference internal" href="#module-bdb" title="bdb: Debugger framework."><code>bdb</code></a> module also defines two classes:</p> <dl class="py class"> <dt class="sig sig-object py" id="bdb.Breakpoint">
<code>class bdb.Breakpoint(self, file, line, temporary=False, cond=None, funcname=None)</code> </dt> <dd>
<p>This class implements temporary breakpoints, ignore counts, disabling and (re-)enabling, and conditionals.</p> <p>Breakpoints are indexed by number through a list called <a class="reference internal" href="#bdb.Breakpoint.bpbynumber" title="bdb.Breakpoint.bpbynumber"><code>bpbynumber</code></a> and by <code>(file, line)</code> pairs through <a class="reference internal" href="#bdb.Breakpoint.bplist" title="bdb.Breakpoint.bplist"><code>bplist</code></a>. The former points to a single instance of class <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a>. The latter points to a list of such instances since there may be more than one breakpoint per line.</p> <p>When creating a breakpoint, its associated <a class="reference internal" href="#bdb.Breakpoint.file" title="bdb.Breakpoint.file"><code>file name</code></a> should be in canonical form. If a <a class="reference internal" href="#bdb.Breakpoint.funcname" title="bdb.Breakpoint.funcname"><code>funcname</code></a> is defined, a breakpoint <a class="reference internal" href="#bdb.Breakpoint.hits" title="bdb.Breakpoint.hits"><code>hit</code></a> will be counted when the first line of that function is executed. A <a class="reference internal" href="#bdb.Breakpoint.cond" title="bdb.Breakpoint.cond"><code>conditional</code></a> breakpoint always counts a <a class="reference internal" href="#bdb.Breakpoint.hits" title="bdb.Breakpoint.hits"><code>hit</code></a>.</p> <p><a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> instances have the following methods:</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Breakpoint.deleteMe">
<code>deleteMe()</code> </dt> <dd>
<p>Delete the breakpoint from the list associated to a file/line. If it is the last breakpoint in that position, it also deletes the entry for the file/line.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Breakpoint.enable">
<code>enable()</code> </dt> <dd>
<p>Mark the breakpoint as enabled.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Breakpoint.disable">
<code>disable()</code> </dt> <dd>
<p>Mark the breakpoint as disabled.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Breakpoint.bpformat">
<code>bpformat()</code> </dt> <dd>
<p>Return a string with all the information about the breakpoint, nicely formatted:</p> <ul class="simple"> <li>Breakpoint number.</li> <li>Temporary status (del or keep).</li> <li>File/line position.</li> <li>Break condition.</li> <li>Number of times to ignore.</li> <li>Number of times hit.</li> </ul> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.2.</span></p> </div> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Breakpoint.bpprint">
<code>bpprint(out=None)</code> </dt> <dd>
<p>Print the output of <a class="reference internal" href="#bdb.Breakpoint.bpformat" title="bdb.Breakpoint.bpformat"><code>bpformat()</code></a> to the file <em>out</em>, or if it is <code>None</code>, to standard output.</p> </dd>
</dl> <p><a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> instances have the following attributes:</p> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.file">
<code>file</code> </dt> <dd>
<p>File name of the <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a>.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.line">
<code>line</code> </dt> <dd>
<p>Line number of the <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> within <a class="reference internal" href="#bdb.Breakpoint.file" title="bdb.Breakpoint.file"><code>file</code></a>.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.temporary">
<code>temporary</code> </dt> <dd>
<p>True if a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> at (file, line) is temporary.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.cond">
<code>cond</code> </dt> <dd>
<p>Condition for evaluating a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> at (file, line).</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.funcname">
<code>funcname</code> </dt> <dd>
<p>Function name that defines whether a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> is hit upon entering the function.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.enabled">
<code>enabled</code> </dt> <dd>
<p>True if <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> is enabled.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.bpbynumber">
<code>bpbynumber</code> </dt> <dd>
<p>Numeric index for a single instance of a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a>.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.bplist">
<code>bplist</code> </dt> <dd>
<p>Dictionary of <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> instances indexed by (<a class="reference internal" href="#bdb.Breakpoint.file" title="bdb.Breakpoint.file"><code>file</code></a>, <a class="reference internal" href="#bdb.Breakpoint.line" title="bdb.Breakpoint.line"><code>line</code></a>) tuples.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.ignore">
<code>ignore</code> </dt> <dd>
<p>Number of times to ignore a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a>.</p> </dd>
</dl> <dl class="py attribute"> <dt class="sig sig-object py" id="bdb.Breakpoint.hits">
<code>hits</code> </dt> <dd>
<p>Count of the number of times a <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> has been hit.</p> </dd>
</dl> </dd>
</dl> <dl class="py class"> <dt class="sig sig-object py" id="bdb.Bdb">
<code>class bdb.Bdb(skip=None)</code> </dt> <dd>
<p>The <a class="reference internal" href="#bdb.Bdb" title="bdb.Bdb"><code>Bdb</code></a> class acts as a generic Python debugger base class.</p> <p>This class takes care of the details of the trace facility; a derived class should implement user interaction. The standard debugger class (<a class="reference internal" href="pdb#pdb.Pdb" title="pdb.Pdb"><code>pdb.Pdb</code></a>) is an example.</p> <p>The <em>skip</em> 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. Whether a frame is considered to originate in a certain module is determined by the <code>__name__</code> in the frame globals.</p> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.1: </span>The <em>skip</em> argument.</p> </div> <p>The following methods of <a class="reference internal" href="#bdb.Bdb" title="bdb.Bdb"><code>Bdb</code></a> normally don’t need to be overridden.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.canonic">
<code>canonic(filename)</code> </dt> <dd>
<p>Return canonical form of <em>filename</em>.</p> <p>For real file names, the canonical form is an operating-system-dependent, <a class="reference internal" href="os.path#os.path.normcase" title="os.path.normcase"><code>case-normalized</code></a> <a class="reference internal" href="os.path#os.path.abspath" title="os.path.abspath"><code>absolute path</code></a>. A <em>filename</em> with angle brackets, such as <code>"&lt;stdin&gt;"</code> generated in interactive mode, is returned unchanged.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.reset">
<code>reset()</code> </dt> <dd>
<p>Set the <code>botframe</code>, <code>stopframe</code>, <code>returnframe</code> and <code>quitting</code> attributes with values ready to start debugging.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.trace_dispatch">
<code>trace_dispatch(frame, event, arg)</code> </dt> <dd>
<p>This function is installed as the trace function of debugged frames. Its return value is the new trace function (in most cases, that is, itself).</p> <p>The default implementation decides how to dispatch a frame, depending on the type of event (passed as a string) that is about to be executed. <em>event</em> can be one of the following:</p> <ul class="simple"> <li>
<code>"line"</code>: A new line of code is going to be executed.</li> <li>
<code>"call"</code>: A function is about to be called, or another code block entered.</li> <li>
<code>"return"</code>: A function or other code block is about to return.</li> <li>
<code>"exception"</code>: An exception has occurred.</li> <li>
<code>"c_call"</code>: A C function is about to be called.</li> <li>
<code>"c_return"</code>: A C function has returned.</li> <li>
<code>"c_exception"</code>: A C function has raised an exception.</li> </ul> <p>For the Python events, specialized functions (see below) are called. For the C events, no action is taken.</p> <p>The <em>arg</em> parameter depends on the previous event.</p> <p>See the documentation for <a class="reference internal" href="sys#sys.settrace" title="sys.settrace"><code>sys.settrace()</code></a> for more information on the trace function. For more information on code and frame objects, refer to <a class="reference internal" href="../reference/datamodel#types"><span class="std std-ref">The standard type hierarchy</span></a>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.dispatch_line">
<code>dispatch_line(frame)</code> </dt> <dd>
<p>If the debugger should stop on the current line, invoke the <a class="reference internal" href="#bdb.Bdb.user_line" title="bdb.Bdb.user_line"><code>user_line()</code></a> method (which should be overridden in subclasses). Raise a <a class="reference internal" href="#bdb.BdbQuit" title="bdb.BdbQuit"><code>BdbQuit</code></a> exception if the <code>Bdb.quitting</code> flag is set (which can be set from <a class="reference internal" href="#bdb.Bdb.user_line" title="bdb.Bdb.user_line"><code>user_line()</code></a>). Return a reference to the <a class="reference internal" href="#bdb.Bdb.trace_dispatch" title="bdb.Bdb.trace_dispatch"><code>trace_dispatch()</code></a> method for further tracing in that scope.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.dispatch_call">
<code>dispatch_call(frame, arg)</code> </dt> <dd>
<p>If the debugger should stop on this function call, invoke the <a class="reference internal" href="#bdb.Bdb.user_call" title="bdb.Bdb.user_call"><code>user_call()</code></a> method (which should be overridden in subclasses). Raise a <a class="reference internal" href="#bdb.BdbQuit" title="bdb.BdbQuit"><code>BdbQuit</code></a> exception if the <code>Bdb.quitting</code> flag is set (which can be set from <a class="reference internal" href="#bdb.Bdb.user_call" title="bdb.Bdb.user_call"><code>user_call()</code></a>). Return a reference to the <a class="reference internal" href="#bdb.Bdb.trace_dispatch" title="bdb.Bdb.trace_dispatch"><code>trace_dispatch()</code></a> method for further tracing in that scope.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.dispatch_return">
<code>dispatch_return(frame, arg)</code> </dt> <dd>
<p>If the debugger should stop on this function return, invoke the <a class="reference internal" href="#bdb.Bdb.user_return" title="bdb.Bdb.user_return"><code>user_return()</code></a> method (which should be overridden in subclasses). Raise a <a class="reference internal" href="#bdb.BdbQuit" title="bdb.BdbQuit"><code>BdbQuit</code></a> exception if the <code>Bdb.quitting</code> flag is set (which can be set from <a class="reference internal" href="#bdb.Bdb.user_return" title="bdb.Bdb.user_return"><code>user_return()</code></a>). Return a reference to the <a class="reference internal" href="#bdb.Bdb.trace_dispatch" title="bdb.Bdb.trace_dispatch"><code>trace_dispatch()</code></a> method for further tracing in that scope.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.dispatch_exception">
<code>dispatch_exception(frame, arg)</code> </dt> <dd>
<p>If the debugger should stop at this exception, invokes the <a class="reference internal" href="#bdb.Bdb.user_exception" title="bdb.Bdb.user_exception"><code>user_exception()</code></a> method (which should be overridden in subclasses). Raise a <a class="reference internal" href="#bdb.BdbQuit" title="bdb.BdbQuit"><code>BdbQuit</code></a> exception if the <code>Bdb.quitting</code> flag is set (which can be set from <a class="reference internal" href="#bdb.Bdb.user_exception" title="bdb.Bdb.user_exception"><code>user_exception()</code></a>). Return a reference to the <a class="reference internal" href="#bdb.Bdb.trace_dispatch" title="bdb.Bdb.trace_dispatch"><code>trace_dispatch()</code></a> method for further tracing in that scope.</p> </dd>
</dl> <p>Normally derived classes don’t override the following methods, but they may if they want to redefine the definition of stopping and breakpoints.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.is_skipped_line">
<code>is_skipped_line(module_name)</code> </dt> <dd>
<p>Return True if <em>module_name</em> matches any skip pattern.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.stop_here">
<code>stop_here(frame)</code> </dt> <dd>
<p>Return True if <em>frame</em> is below the starting frame in the stack.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.break_here">
<code>break_here(frame)</code> </dt> <dd>
<p>Return True if there is an effective breakpoint for this line.</p> <p>Check whether a line or function breakpoint exists and is in effect. Delete temporary breakpoints based on information from <a class="reference internal" href="#bdb.effective" title="bdb.effective"><code>effective()</code></a>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.break_anywhere">
<code>break_anywhere(frame)</code> </dt> <dd>
<p>Return True if any breakpoint exists for <em>frame</em>’s filename.</p> </dd>
</dl> <p>Derived classes should override these methods to gain control over debugger operation.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.user_call">
<code>user_call(frame, argument_list)</code> </dt> <dd>
<p>Called from <a class="reference internal" href="#bdb.Bdb.dispatch_call" title="bdb.Bdb.dispatch_call"><code>dispatch_call()</code></a> if a break might stop inside the called function.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.user_line">
<code>user_line(frame)</code> </dt> <dd>
<p>Called from <a class="reference internal" href="#bdb.Bdb.dispatch_line" title="bdb.Bdb.dispatch_line"><code>dispatch_line()</code></a> when either <a class="reference internal" href="#bdb.Bdb.stop_here" title="bdb.Bdb.stop_here"><code>stop_here()</code></a> or <a class="reference internal" href="#bdb.Bdb.break_here" title="bdb.Bdb.break_here"><code>break_here()</code></a> returns <code>True</code>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.user_return">
<code>user_return(frame, return_value)</code> </dt> <dd>
<p>Called from <a class="reference internal" href="#bdb.Bdb.dispatch_return" title="bdb.Bdb.dispatch_return"><code>dispatch_return()</code></a> when <a class="reference internal" href="#bdb.Bdb.stop_here" title="bdb.Bdb.stop_here"><code>stop_here()</code></a> returns <code>True</code>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.user_exception">
<code>user_exception(frame, exc_info)</code> </dt> <dd>
<p>Called from <a class="reference internal" href="#bdb.Bdb.dispatch_exception" title="bdb.Bdb.dispatch_exception"><code>dispatch_exception()</code></a> when <a class="reference internal" href="#bdb.Bdb.stop_here" title="bdb.Bdb.stop_here"><code>stop_here()</code></a> returns <code>True</code>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.do_clear">
<code>do_clear(arg)</code> </dt> <dd>
<p>Handle how a breakpoint must be removed when it is a temporary one.</p> <p>This method must be implemented by derived classes.</p> </dd>
</dl> <p>Derived classes and clients can call the following methods to affect the stepping state.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_step">
<code>set_step()</code> </dt> <dd>
<p>Stop after one line of code.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_next">
<code>set_next(frame)</code> </dt> <dd>
<p>Stop on the next line in or below the given frame.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_return">
<code>set_return(frame)</code> </dt> <dd>
<p>Stop when returning from the given frame.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_until">
<code>set_until(frame, lineno=None)</code> </dt> <dd>
<p>Stop when the line with the <em>lineno</em> greater than the current one is reached or when returning from current frame.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_trace">
<code>set_trace([frame])</code> </dt> <dd>
<p>Start debugging from <em>frame</em>. If <em>frame</em> is not specified, debugging starts from caller’s frame.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_continue">
<code>set_continue()</code> </dt> <dd>
<p>Stop only at breakpoints or when finished. If there are no breakpoints, set the system trace function to <code>None</code>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_quit">
<code>set_quit()</code> </dt> <dd>
<p>Set the <code>quitting</code> attribute to <code>True</code>. This raises <a class="reference internal" href="#bdb.BdbQuit" title="bdb.BdbQuit"><code>BdbQuit</code></a> in the next call to one of the <code>dispatch_*()</code> methods.</p> </dd>
</dl> <p>Derived classes and clients can call the following methods to manipulate breakpoints. These methods return a string containing an error message if something went wrong, or <code>None</code> if all is well.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.set_break">
<code>set_break(filename, lineno, temporary=False, cond=None, funcname=None)</code> </dt> <dd>
<p>Set a new breakpoint. If the <em>lineno</em> line doesn’t exist for the <em>filename</em> passed as argument, return an error message. The <em>filename</em> should be in canonical form, as described in the <a class="reference internal" href="#bdb.Bdb.canonic" title="bdb.Bdb.canonic"><code>canonic()</code></a> method.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.clear_break">
<code>clear_break(filename, lineno)</code> </dt> <dd>
<p>Delete the breakpoints in <em>filename</em> and <em>lineno</em>. If none were set, return an error message.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.clear_bpbynumber">
<code>clear_bpbynumber(arg)</code> </dt> <dd>
<p>Delete the breakpoint which has the index <em>arg</em> in the <a class="reference internal" href="#bdb.Breakpoint.bpbynumber" title="bdb.Breakpoint.bpbynumber"><code>Breakpoint.bpbynumber</code></a>. If <em>arg</em> is not numeric or out of range, return an error message.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.clear_all_file_breaks">
<code>clear_all_file_breaks(filename)</code> </dt> <dd>
<p>Delete all breakpoints in <em>filename</em>. If none were set, return an error message.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.clear_all_breaks">
<code>clear_all_breaks()</code> </dt> <dd>
<p>Delete all existing breakpoints. If none were set, return an error message.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_bpbynumber">
<code>get_bpbynumber(arg)</code> </dt> <dd>
<p>Return a breakpoint specified by the given number. If <em>arg</em> is a string, it will be converted to a number. If <em>arg</em> is a non-numeric string, if the given breakpoint never existed or has been deleted, a <a class="reference internal" href="exceptions#ValueError" title="ValueError"><code>ValueError</code></a> is raised.</p> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.2.</span></p> </div> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_break">
<code>get_break(filename, lineno)</code> </dt> <dd>
<p>Return True if there is a breakpoint for <em>lineno</em> in <em>filename</em>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_breaks">
<code>get_breaks(filename, lineno)</code> </dt> <dd>
<p>Return all breakpoints for <em>lineno</em> in <em>filename</em>, or an empty list if none are set.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_file_breaks">
<code>get_file_breaks(filename)</code> </dt> <dd>
<p>Return all breakpoints in <em>filename</em>, or an empty list if none are set.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_all_breaks">
<code>get_all_breaks()</code> </dt> <dd>
<p>Return all breakpoints that are set.</p> </dd>
</dl> <p>Derived classes and clients can call the following methods to get a data structure representing a stack trace.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.get_stack">
<code>get_stack(f, t)</code> </dt> <dd>
<p>Return a list of (frame, lineno) tuples in a stack trace, and a size.</p> <p>The most recently called frame is last in the list. The size is the number of frames below the frame where the debugger was invoked.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.format_stack_entry">
<code>format_stack_entry(frame_lineno, lprefix=': ')</code> </dt> <dd>
<p>Return a string with information about a stack entry, which is a <code>(frame, lineno)</code> tuple. The return string contains:</p> <ul class="simple"> <li>The canonical filename which contains the frame.</li> <li>The function name or <code>"&lt;lambda&gt;"</code>.</li> <li>The input arguments.</li> <li>The return value.</li> <li>The line of code (if it exists).</li> </ul> </dd>
</dl> <p>The following two methods can be called by clients to use a debugger to debug a <a class="reference internal" href="../glossary#term-statement"><span class="xref std std-term">statement</span></a>, given as a string.</p> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.run">
<code>run(cmd, globals=None, locals=None)</code> </dt> <dd>
<p>Debug a statement executed via the <a class="reference internal" href="functions#exec" title="exec"><code>exec()</code></a> function. <em>globals</em> defaults to <code>__main__.__dict__</code>, <em>locals</em> defaults to <em>globals</em>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.runeval">
<code>runeval(expr, globals=None, locals=None)</code> </dt> <dd>
<p>Debug an expression executed via the <a class="reference internal" href="functions#eval" title="eval"><code>eval()</code></a> function. <em>globals</em> and <em>locals</em> have the same meaning as in <a class="reference internal" href="#bdb.Bdb.run" title="bdb.Bdb.run"><code>run()</code></a>.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.runctx">
<code>runctx(cmd, globals, locals)</code> </dt> <dd>
<p>For backwards compatibility. Calls the <a class="reference internal" href="#bdb.Bdb.run" title="bdb.Bdb.run"><code>run()</code></a> method.</p> </dd>
</dl> <dl class="py method"> <dt class="sig sig-object py" id="bdb.Bdb.runcall">
<code>runcall(func, /, *args, **kwds)</code> </dt> <dd>
<p>Debug a single function call, and return its result.</p> </dd>
</dl> </dd>
</dl> <p>Finally, the module defines the following functions:</p> <dl class="py function"> <dt class="sig sig-object py" id="bdb.checkfuncname">
<code>bdb.checkfuncname(b, frame)</code> </dt> <dd>
<p>Return True if we should break here, depending on the way the <a class="reference internal" href="#bdb.Breakpoint" title="bdb.Breakpoint"><code>Breakpoint</code></a> <em>b</em> was set.</p> <p>If it was set via line number, it checks if <a class="reference internal" href="#bdb.Breakpoint.line" title="bdb.Breakpoint.line"><code>b.line</code></a> is the same as the one in <em>frame</em>. If the breakpoint was set via <a class="reference internal" href="#bdb.Breakpoint.funcname" title="bdb.Breakpoint.funcname"><code>function name</code></a>, we have to check we are in the right <em>frame</em> (the right function) and if we are on its first executable line.</p> </dd>
</dl> <dl class="py function"> <dt class="sig sig-object py" id="bdb.effective">
<code>bdb.effective(file, line, frame)</code> </dt> <dd>
<p>Return <code>(active breakpoint, delete temporary flag)</code> or <code>(None, None)</code> as the breakpoint to act upon.</p> <p>The <em>active breakpoint</em> is the first entry in <a class="reference internal" href="#bdb.Breakpoint.bplist" title="bdb.Breakpoint.bplist"><code>bplist</code></a> for the (<a class="reference internal" href="#bdb.Breakpoint.file" title="bdb.Breakpoint.file"><code>file</code></a>, <a class="reference internal" href="#bdb.Breakpoint.line" title="bdb.Breakpoint.line"><code>line</code></a>) (which must exist) that is <a class="reference internal" href="#bdb.Breakpoint.enabled" title="bdb.Breakpoint.enabled"><code>enabled</code></a>, for which <a class="reference internal" href="#bdb.checkfuncname" title="bdb.checkfuncname"><code>checkfuncname()</code></a> is True, and that has neither a False <a class="reference internal" href="#bdb.Breakpoint.cond" title="bdb.Breakpoint.cond"><code>condition</code></a> nor positive <a class="reference internal" href="#bdb.Breakpoint.ignore" title="bdb.Breakpoint.ignore"><code>ignore</code></a> count. The <em>flag</em>, meaning that a temporary breakpoint should be deleted, is False only when the <a class="reference internal" href="#bdb.Breakpoint.cond" title="bdb.Breakpoint.cond"><code>cond</code></a> cannot be evaluated (in which case, <a class="reference internal" href="#bdb.Breakpoint.ignore" title="bdb.Breakpoint.ignore"><code>ignore</code></a> count is ignored).</p> <p>If no such entry exists, then (None, None) is returned.</p> </dd>
</dl> <dl class="py function"> <dt class="sig sig-object py" id="bdb.set_trace">
<code>bdb.set_trace()</code> </dt> <dd>
<p>Start debugging with a <a class="reference internal" href="#bdb.Bdb" title="bdb.Bdb"><code>Bdb</code></a> instance from caller’s frame.</p> </dd>
</dl> <div class="_attribution">
  <p class="_attribution-p">
    &copy; 2001&ndash;2023 Python Software Foundation<br>Licensed under the PSF License.<br>
    <a href="https://docs.python.org/3.12/library/bdb.html" class="_attribution-link">https://docs.python.org/3.12/library/bdb.html</a>
  </p>
</div>