"""
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)