6. cStringIO
— Faster version of StringIO
¶
The module cStringIO
provides an interface similar to that of the
StringIO
module. Heavy use of StringIO.StringIO
objects can be
made more efficient by using the function StringIO()
from this module
instead.
-
cStringIO.
StringIO
([s])¶ Return a StringIO-like stream for reading or writing.
Since this is a factory function which returns objects of built-in types, there’s no way to build your own version using subclassing. It’s not possible to set attributes on it. Use the original
StringIO
module in those cases.Unlike the
StringIO
module, this module is not able to accept Unicode strings that cannot be encoded as plain ASCII strings.Another difference from the
StringIO
module is that callingStringIO()
with a string parameter creates a read-only object. Unlike an object created without a string parameter, it does not have write methods. These objects are not generally visible. They turn up in tracebacks asStringI
andStringO
.
The following data objects are provided as well:
-
cStringIO.
InputType
¶ The type object of the objects created by calling
StringIO()
with a string parameter.
-
cStringIO.
OutputType
¶ The type object of the objects returned by calling
StringIO()
with no parameters.
There is a C API to the module as well; refer to the module source for more information.
Example usage:
import cStringIO
output = cStringIO.StringIO()
output.write('First line.\n')
print >>output, 'Second line.'
# Retrieve file contents -- this will be
# 'First line.\nSecond line.\n'
contents = output.getvalue()
# Close object and discard memory buffer --
# .getvalue() will now raise an exception.
output.close()