Vega strike Python Modules doc: traceback Namespace Reference

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Functions
def	print_list

def	format_list

def	print_tb

def	format_tb

def	extract_tb

def	print_exception

def	format_exception

def	format_exception_only

def	print_exc

def	print_last

def	print_stack

def	format_stack

def	extract_stack

def	tb_lineno

Variables
list	__all__

Detailed Description

Extract, format and print information about Python stack traces.

Function Documentation

def traceback.extract_stack	(	f = `None`,
		limit = `None`
	)

Extract the raw traceback from the current stack frame.

The return value has the same format as for extract_tb().  The
optional 'f' and 'limit' arguments have the same meaning as for
print_stack().  Each item in the list is a quadruple (filename,
line number, function name, text), and the entries are in order
from oldest to newest stack frame.

Definition at line 246 of file traceback.py.

References linecache.getline().

 
 def extract_stack(f=None, limit = None):
     """Extract the raw traceback from the current stack frame.
 
     The return value has the same format as for extract_tb().  The
     optional 'f' and 'limit' arguments have the same meaning as for
     print_stack().  Each item in the list is a quadruple (filename,
     line number, function name, text), and the entries are in order
     from oldest to newest stack frame.
     """
     if f is None:
         try:
             raise ZeroDivisionError
         except ZeroDivisionError:
             f = sys.exc_info()[2].tb_frame.f_back
     if limit is None:
         if hasattr(sys, 'tracebacklimit'):
             limit = sys.tracebacklimit
     list = []
     n = 0
     while f is not None and (limit is None or n < limit):
         lineno = f.f_lineno     # XXX Too bad if -O is used
         co = f.f_code
         filename = co.co_filename
         name = co.co_name
         line = linecache.getline(filename, lineno)
         if line: line = line.strip()
         else: line = None
         list.append((filename, lineno, name, line))
         f = f.f_back
         n = n+1
     list.reverse()
     return list

def traceback.extract_tb	(	tb,
		limit = `None`
	)

Return list of up to limit pre-processed entries from traceback.

This is useful for alternate formatting of stack traces.  If
'limit' is omitted or None, all entries are extracted.  A
pre-processed stack trace entry is a quadruple (filename, line
number, function name, text) representing the information that is
usually printed for a stack trace.  The text is a string with
leading and trailing whitespace stripped; if the source is not
available it is None.

Definition at line 77 of file traceback.py.

References linecache.getline(), and tb_lineno().

 
 def extract_tb(tb, limit = None):
     """Return list of up to limit pre-processed entries from traceback.
 
     This is useful for alternate formatting of stack traces.  If
     'limit' is omitted or None, all entries are extracted.  A
     pre-processed stack trace entry is a quadruple (filename, line
     number, function name, text) representing the information that is
     usually printed for a stack trace.  The text is a string with
     leading and trailing whitespace stripped; if the source is not
     available it is None.
     """
     if limit is None:
         if hasattr(sys, 'tracebacklimit'):
             limit = sys.tracebacklimit
     list = []
     n = 0
     while tb is not None and (limit is None or n < limit):
         f = tb.tb_frame
         lineno = tb_lineno(tb)
         co = f.f_code
         filename = co.co_filename
         name = co.co_name
         line = linecache.getline(filename, lineno)
         if line: line = line.strip()
         else: line = None
         list.append((filename, lineno, name, line))
         tb = tb.tb_next
         n = n+1
     return list
 

def traceback.format_exception	(	etype,
		value,
		tb,
		limit = `None`
	)

Format a stack trace and the exception information.

The arguments have the same meaning as the corresponding arguments
to print_exception().  The return value is a list of strings, each
ending in a newline and some containing internal newlines.  When
these lines are concatenated and printed, exactly the same text is
printed as does print_exception().

Definition at line 129 of file traceback.py.

References format_exception_only(), and format_tb().

 
 def format_exception(etype, value, tb, limit = None):
     """Format a stack trace and the exception information.
 
     The arguments have the same meaning as the corresponding arguments
     to print_exception().  The return value is a list of strings, each
     ending in a newline and some containing internal newlines.  When
     these lines are concatenated and printed, exactly the same text is
     printed as does print_exception().
     """
     if tb:
         list = ['Traceback (most recent call last):\n']
         list = list + format_tb(tb, limit)
     else:
         list = []
     list = list + format_exception_only(etype, value)
     return list

def traceback.format_exception_only	(	etype,
		value
	)

Format the exception part of a traceback.

The arguments are the exception type and value such as given by
sys.last_type and sys.last_value. The return value is a list of
strings, each ending in a newline.  Normally, the list contains a
single string; however, for SyntaxError exceptions, it contains
several lines that (when printed) display detailed information
about where the syntax error occurred.  The message indicating
which exception occurred is the always last string in the list.

Definition at line 146 of file traceback.py.

References locale.str().

 
 def format_exception_only(etype, value):
     """Format the exception part of a traceback.
 
     The arguments are the exception type and value such as given by
     sys.last_type and sys.last_value. The return value is a list of
     strings, each ending in a newline.  Normally, the list contains a
     single string; however, for SyntaxError exceptions, it contains
     several lines that (when printed) display detailed information
     about where the syntax error occurred.  The message indicating
     which exception occurred is the always last string in the list.
     """
     list = []
     if type(etype) == types.ClassType:
         stype = etype.__name__
     else:
         stype = etype
     if value is None:
         list.append(str(stype) + '\n')
     else:
         if etype is SyntaxError:
             try:
                 msg, (filename, lineno, offset, line) = value
             except:
                 pass
             else:
                 if not filename: filename = "<string>"
                 list.append('  File "%s", line %d\n' %
                             (filename, lineno))
                 if line is not None:
                     i = 0
                     while i < len(line) and line[i].isspace():
                         i = i+1
                     list.append('    %s\n' % line.strip())
                     if offset is not None:
                         s = '    '
                         for c in line[i:offset-1]:
                             if c.isspace():
                                 s = s + c
                             else:
                                 s = s + ' '
                         list.append('%s^\n' % s)
                     value = msg
         s = _some_str(value)
         if s:
             list.append('%s: %s\n' % (str(stype), s))
         else:
             list.append('%s\n' % str(stype))
     return list

def traceback.format_list ( extracted_list)

Format a list of traceback entry tuples for printing.

Given a list of tuples as returned by extract_tb() or
extract_stack(), return a list of strings ready for printing.
Each string in the resulting list corresponds to the item with the
same index in the argument list.  Each string ends in a newline;
the strings may contain internal newlines as well, for those items
whose source text line is not None.

Definition at line 27 of file traceback.py.

 
 def format_list(extracted_list):
     """Format a list of traceback entry tuples for printing.
 
     Given a list of tuples as returned by extract_tb() or
     extract_stack(), return a list of strings ready for printing.
     Each string in the resulting list corresponds to the item with the
     same index in the argument list.  Each string ends in a newline;
     the strings may contain internal newlines as well, for those items
     whose source text line is not None.
     """
     list = []
     for filename, lineno, name, line in extracted_list:
         item = '  File "%s", line %d, in %s\n' % (filename,lineno,name)
         if line:
             item = item + '    %s\n' % line.strip()
         list.append(item)
     return list
 

def traceback.print_exc	(	limit = `None`,
		file = `None`
	)

Shorthand for 'print_exception(sys.exc_type, sys.exc_value, sys.exc_traceback, limit, file)'.
(In fact, it uses sys.exc_info() to retrieve the same information
in a thread-safe way.)

Definition at line 202 of file traceback.py.

References print_exception().

 
 def print_exc(limit=None, file=None):
     """Shorthand for 'print_exception(sys.exc_type, sys.exc_value, sys.exc_traceback, limit, file)'.
     (In fact, it uses sys.exc_info() to retrieve the same information
     in a thread-safe way.)"""
     if not file:
         file = sys.stderr
     try:
         etype, value, tb = sys.exc_info()
         print_exception(etype, value, tb, limit, file)
     finally:
         etype = value = tb = None

def traceback.print_exception	(	etype,
		value,
		tb,
		limit = `None`,
		file = `None`
	)

Print exception up to 'limit' stack trace entries from 'tb' to 'file'.

This differs from print_tb() in the following ways: (1) if
traceback is not None, it prints a header "Traceback (most recent
call last):"; (2) it prints the exception type and value after the
stack trace; (3) if type is SyntaxError and value has the
appropriate format, it prints the line where the syntax error
occurred with a caret on the next line indicating the approximate
position of the error.

Definition at line 108 of file traceback.py.

References format_exception_only(), and print_tb().

 
 def print_exception(etype, value, tb, limit=None, file=None):
     """Print exception up to 'limit' stack trace entries from 'tb' to 'file'.
 
     This differs from print_tb() in the following ways: (1) if
     traceback is not None, it prints a header "Traceback (most recent
     call last):"; (2) it prints the exception type and value after the
     stack trace; (3) if type is SyntaxError and value has the
     appropriate format, it prints the line where the syntax error
     occurred with a caret on the next line indicating the approximate
     position of the error.
     """
     if not file:
         file = sys.stderr
     if tb:
         _print(file, 'Traceback (most recent call last):')
         print_tb(tb, limit, file)
     lines = format_exception_only(etype, value)
     for line in lines[:-1]:
         _print(file, line, ' ')
     _print(file, lines[-1], '')

def traceback.print_last	(	limit = `None`,
		file = `None`
	)

This is a shorthand for 'print_exception(sys.last_type,
sys.last_value, sys.last_traceback, limit, file)'.

Definition at line 214 of file traceback.py.

References print_exception().

 
 def print_last(limit=None, file=None):
     """This is a shorthand for 'print_exception(sys.last_type,
     sys.last_value, sys.last_traceback, limit, file)'."""
     if not file:
         file = sys.stderr
     print_exception(sys.last_type, sys.last_value, sys.last_traceback,
                     limit, file)
 

def traceback.print_stack	(	f = `None`,
		limit = `None`,
		file = `None`
	)

Print a stack trace from its invocation point.

The optional 'f' argument can be used to specify an alternate
stack frame at which to start. The optional 'limit' and 'file'
arguments have the same meaning as for print_exception().

Definition at line 223 of file traceback.py.

References extract_stack(), and print_list().

 
 def print_stack(f=None, limit=None, file=None):
     """Print a stack trace from its invocation point.
 
     The optional 'f' argument can be used to specify an alternate
     stack frame at which to start. The optional 'limit' and 'file'
     arguments have the same meaning as for print_exception().
     """
     if f is None:
         try:
             raise ZeroDivisionError
         except ZeroDivisionError:
             f = sys.exc_info()[2].tb_frame.f_back
     print_list(extract_stack(f, limit), file)

def traceback.print_tb	(	tb,
		limit = `None`,
		file = `None`
	)

Print up to 'limit' stack trace entries from the traceback 'tb'.

If 'limit' is omitted or None, all entries are printed.  If 'file'
is omitted or None, the output goes to sys.stderr; otherwise
'file' should be an open file or file-like object with a write()
method.

Definition at line 46 of file traceback.py.

References linecache.getline(), and tb_lineno().

 
 def print_tb(tb, limit=None, file=None):
     """Print up to 'limit' stack trace entries from the traceback 'tb'.
 
     If 'limit' is omitted or None, all entries are printed.  If 'file'
     is omitted or None, the output goes to sys.stderr; otherwise
     'file' should be an open file or file-like object with a write()
     method.
     """
     if not file:
         file = sys.stderr
     if limit is None:
         if hasattr(sys, 'tracebacklimit'):
             limit = sys.tracebacklimit
     n = 0
     while tb is not None and (limit is None or n < limit):
         f = tb.tb_frame
         lineno = tb_lineno(tb)
         co = f.f_code
         filename = co.co_filename
         name = co.co_name
         _print(file,
                '  File "%s", line %d, in %s' % (filename,lineno,name))
         line = linecache.getline(filename, lineno)
         if line: _print(file, '    ' + line.strip())
         tb = tb.tb_next
         n = n+1

def traceback.tb_lineno ( tb)

Calculate correct line number of traceback given in tb.

Even works with -O on.

Definition at line 279 of file traceback.py.

 
 def tb_lineno(tb):
     """Calculate correct line number of traceback given in tb.
 
     Even works with -O on.
     """
     # Coded by Marc-Andre Lemburg from the example of PyCode_Addr2Line()
     # in compile.c.
     # Revised version by Jim Hugunin to work with JPython too.
 
     c = tb.tb_frame.f_code
     if not hasattr(c, 'co_lnotab'):
         return tb.tb_lineno
 
     tab = c.co_lnotab
     line = c.co_firstlineno
     stopat = tb.tb_lasti
     addr = 0
     for i in range(0, len(tab), 2):
         addr = addr + ord(tab[i])
         if addr > stopat:
             break
         line = line + ord(tab[i+1])
     return line

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation