Here is my proposal which hopefully would settle the issue to rest
class List(list):
"""
>>> a=List()
>>> for i in range(100000): a.append(i)
>>> print a.first
0
>>> print a.second
1
>>> print a.third
2
>>> print a.twentieth
19
>>> print a.twentysecond
21
>>> print a.onehundredthirtyfifth
134
>>> print a.onethousandfivehundredandthirtyeighth
1537
"""
def __getattr__(self,name):
import re
if name.endswith('first'): name = name[:-5]+'one'
elif name.endswith('second'): name = name[:-6]+'two'
elif name.endswith('third'): name = name[:-5]+'three'
elif name.endswith('fth'): name = name[:-3]+'ve'
elif name.endswith('hth'): name = name[:-3]+'th'
elif name.endswith('ieth'): name = name[:-4]+'y'
elif name.endswith('th'): name = name[:-2]
subs = {
'one':'+1',
'two':'+2',
'three':'+3',
'four':'+4',
'five':'+5',
'six':'+6',
'seven':'+7',
'eigth':'+8',
'nine':'+9',
'ten':'+10',
'eleven':'+11',
'twelve':'+12',
'thirteen':'+13',
'fourteen':'+14',
'fiftheen':'+15',
'sixteen':'+16',
'seventeen':'+17',
'eighteen':'+18',
'nineteen':'+19',
'ten':'+10',
'twenty':'+20',
'thirty':'+30',
'fourty':'+40',
'fifthy':'+50',
'sixty':'+60',
'seventy':'+70',
'eighty':'+80',
'ninety':'+90',
'hundred':')*100+(',
'thousand':')*1000+(',
'million':')*1000000+(',
'billion':')*1000000000+(',
'trillion':')*100000000000+(',
'and',''}
for key,value in subs.items(): name = name.replace(key,value)
if '(' in name: name='('+name+')'
name.replace('()','1')
if not re.compile('[\d\+\*\(\)]+').match(name): return AttributeError
try: return self[eval(name)-1]
except: raise AttributeError
I would like to stress that the use of eval in this case is safe as the expression is first validated against a regex.
Massimo