When creating a Decimal from a string, leading and
trailing spaces should be allowed, as it happens with
int and float:

>>> int(' 1 ')
1
>>> Decimal(' 1 ')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/lib/python2.4/decimal.py", line 571, in
__new__
    self._sign, self._int, self._exp =
context._raise_error(ConversionSyntax)
  File "/usr/lib/python2.4/decimal.py", line 2267, in
_raise_error
    raise error, explanation
decimal.InvalidOperation


If we look at decimal.py, the code (regex) is already
there, but commented.

This is a feature request rather than a bug.  There's a least one good 
reason not to do this, namely that the specification on which the decimal 
module is based specifically disallows this:  At

http://www2.hursley.ibm.com/decimal/daconvs.html

it says:  "No blanks or other white space characters are permitted in a 
numeric string.", and the "to-number" operation of the specification, 
which converts strings to Decimal instances, is expected only to accept 
numeric strings.

Of course, all the specification requires is that the functionality of to-
number is present in the Decimal module *somewhere*:  currently it's 
implemented by Decimal.__new__, but it would be possible to alter 
Decimal.__new__ to allow leading and trailing spaces, and have a strictly 
conforming to-number implementation elsewhere in the Decimal module.  I 
don't think there's any real benefit to this.  It's easy enough to add a 
call to strip() to the Decimal argument.

I recommend closing this issue as a "won't fix".

I spoke too soon.  This came up again in the discussion for issue #1780 
and there was general support for allowing trailing and leading 
whitespace.

Fixed for Python 2.6, revision 59929