#!/usr/bin/env python

# $Id: loopmaker.py,v 1.7 2000/04/22 01:44:26 wesc Exp $

#

# loopmaker.py -- CASE script: creates Python loops given parameters

#

# created on 00/04/21 by wesc

#

from keyword import iskeyword

# setup exec_str dictionary

exec_dict = {

# FOR loop

'f': '''

for %s in %s:

print %s

''',

# WHILE loop (sequences)

's': '''

%s = 0

%s = %s

while %s < len(%s):

print %s[%s]

%s = %s + 1

''',

# WHILE loop (numbers)

'n': '''

%s = %d

while %s < %d:

print %s

%s = %s + %d

'''

}

dashes = '\n' + ('-' * 50)

def dashedprint(data, dashes=dashes):

print data + dashes

def main():

# prompt for loop type

while 1:

ltype = raw_input('Loop type? ([F]or/While) ')

if not ltype: ltype = 'f'

if ltype[0] in 'fw':

break

# prompt for data type

while 1:

dtype = raw_input('Data type? ([N]umber/Sequence [str,list,tuple]) ')

if not dtype: dtype = 'n'

if dtype[0] in 'ns':

break

# NUMBER type

if dtype == 'n':

while 1:

start = raw_input('Starting value? [0] ')

if not start:

start = 0

else:

start = int(start)

while 1:

stop = input('Ending value (non-inclusive)? ')

if type(stop) != type(0):

print '*** Ending value must be an integer\n'

else:

break

step = raw_input('Stepping value? [1] ')

if not step:

step = 1

else:

step = int(step)

seq = str(range(start, stop, step))

if seq == '[]':

ans = raw_input('*** Invalid range; change your values? ([y]/n) ')

if not ans or ans[0] == 'y':

continue

print

break

# SEQUENCE type

else:

while 1:

seq = raw_input('Enter sequence (string, list, or tuple): ')

try:

test = eval(seq)

# invalid sequence... reprompt

except SyntaxError:

# keyword can be a string

if iskeyword(seq):

test = seq = `seq`

else:

print "*** Invalid Python sequence data '%s'\n" % seq

continue

# user typed in string without the quotes... add the quotes using repr()

except NameError:

test = seq = `seq`

# must be string, list, or tuple

if type(test) != type('') and type(test) != type([]) and type(test) != type(()):

print "*** Invalid Python sequence data '%s'\n" % seq

continue

break

# iterator variable

while 1:

var = raw_input('Enter iterative variable name? ')

if not var:

print '*** Identifier name is required!\n'

elif iskeyword(var) or var in dir(__builtins__):

print "*** Identifier '%s' name is a keyword or built-in!\n" % var

else:

try:

exec var + '=0'

except SyntaxError:

print "*** Invalid identifier '%s'!\n" % var

continue

break

# FOR loop

if ltype == 'f':

exec_str = exec_dict['f'] % (var, seq, var)

# WHILE loop

elif ltype == 'w':

# sequence length variable (only for sequences)

if dtype == 's':

while 1:

svar = raw_input('Enter sequence name? ')

if not svar:

print '*** Identifier name is required for while loops!\n'

elif iskeyword(svar) or svar in dir(__builtins__):

print "*** Identifier '%s' name is a keyword or built-in!\n" % svar

else:

break

else:

svar = None

# must assign to sequence var if using sequences

if dtype == 's':

exec_str = exec_dict['s'] % (var, svar, seq, var, svar, svar, var, var, var)

# use range() values for loop if using numbers

elif dtype == 'n':

exec_str = exec_dict['n'] % (var, start, var, stop, var, var, var, step)

# EXECUTE code

dashedprint('')

dashedprint('The custom-generated code for you is:')

dashedprint(exec_str)

dashedprint('Test execution of the code:')

exec exec_str

dashedprint('')

# top-level executes main()

if __name__ == '__main__':

print 'Welcome to Loop Maker v1.0\n'

while 1:

main()

try:

again = raw_input('Try again? ([Y]es/No) ')

except:

print

break

if again and again[0] != 'y':

break