_sitebuiltins.py
"""
The objects used by the site module to add custom builtins.
"""
# Those objects are almost immortal and they keep a reference to their module
# globals. Defining them in the site module would keep too many references
# alive.
# Note this means this module should also avoid keep things alive in its
# globals.
import sys
class Quitter(object):
def __init__(self, name, eof):
self.name = name
self.eof = eof
def __repr__(self):
return 'Use %s() or %s to exit' % (self.name, self.eof)
def __call__(self, code=None):
# Shells like IDLE catch the SystemExit, but listen when their
# stdin wrapper is closed.
try:
sys.stdin.close()
except:
pass
raise SystemExit(code)
class _Printer(object):
"""interactive prompt objects for printing the license text, a list of
contributors and the copyright notice."""
MAXLINES = 23
def __init__(self, name, data, files=(), dirs=()):
import os
self.__name = name
self.__data = data
self.__lines = None
self.__filenames = [os.path.join(dir, filename)
for dir in dirs
for filename in files]
def __setup(self):
if self.__lines:
return
data = None
for filename in self.__filenames:
try:
with open(filename, "r") as fp:
data = fp.read()
break
except OSError:
pass
if not data:
data = self.__data
self.__lines = data.split('\n')
self.__linecnt = len(self.__lines)
def __repr__(self):
self.__setup()
if len(self.__lines) <= self.MAXLINES:
return "\n".join(self.__lines)
else:
return "Type %s() to see the full %s text" % ((self.__name,)*2)
def __call__(self):
self.__setup()
prompt = 'Hit Return for more, or q (and Return) to quit: '
lineno = 0
while 1:
try:
for i in range(lineno, lineno + self.MAXLINES):
print(self.__lines[i])
except IndexError:
break
else:
lineno += self.MAXLINES
key = None
while key is None:
key = input(prompt)
if key not in ('', 'q'):
key = None
if key == 'q':
break
class _Helper(object):
"""Define the builtin 'help'.
This is a wrapper around pydoc.help that provides a helpful message
when 'help' is typed at the Python interactive prompt.
Calling help() at the Python prompt starts an interactive help session.
Calling help(thing) prints help for the python object 'thing'.
"""
def __repr__(self):
return "Type help() for interactive help, " \
"or help(object) for help about object."
def __call__(self, *args, **kwds):
import pydoc
return pydoc.help(*args, **kwds)