New module, formats traceback just like the C code does

Lib/traceback.py

@@ -0,0 +1,57 @@
+# Format and print Python stack traces
+
+import linecache
+import string
+import sys
+
+def print_tb(tb, limit = None):
+	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.tb_lineno
+		co = f.f_code
+		filename = co.co_filename
+		name = co.co_name
+		print '  File "%s", line %d, in %s' % (filename, lineno, name)
+		line = linecache.getline(filename, lineno)
+		if line: print '    ' + string.strip(line)
+		tb = tb.tb_next
+		n = n+1
+
+def extract_tb(tb, limit = 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.tb_lineno
+		co = f.f_code
+		filename = co.co_filename
+		name = co.co_name
+		line = linecache.getline(filename, lineno)
+		if line: line = string.strip(line)
+		else: line = None
+		list.append(filename, lineno, name, line)
+		tb = tb.tb_next
+		n = n+1
+	return list
+
+def print_exception(type, value, tb, limit = None):
+	print 'Traceback (innermost last):'
+	print_tb(tb, limit)
+	print type,
+	if value is not None: print ':', value,
+	print
+
+def print_exc(limit = None):
+	print_exception(sys.exc_type, sys.exc_value, sys.exc_traceback,
+			limit)
+
+def print_last(limit = None):
+	print_exception(sys.last_type, sys.last_value, sys.last_traceback,
+			limit)