Michael Chermside wrote:
> Frankly, I have no idea WHAT purpose is served by passing a context
> to the decimal constructor... I didn't even realize it was allowed!
As Tim pointed out, it's solely to control whether or not ConversionSyntax
errors are exceptions or not:
Py> decimal.Decimal("a")
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "c:\python24\lib\decimal.py", line 571, in __new__
self._sign, self._int, self._exp = context._raise_error(ConversionSyntax)
File "c:\python24\lib\decimal.py", line 2266, in _raise_error
raise error, explanation
decimal.InvalidOperation
Py> context = decimal.getcontext().copy()
Py> context.traps[decimal.InvalidOperation] = False
Py> decimal.Decimal("a", context)
Decimal("NaN")
I'm tempted to suggest deprecating the feature, and say if you want invalid
strings to produce NaN, use the create_decimal() method of Context objects.
That
would mean the standard construction operation becomes genuinely context-free.
Being able to supply a context, but then have it be mostly ignored is rather
confusing.
Doing this may also fractionally speed up Decimal creation from strings in the
normal case, as the call to getcontext() could probably be omitted from the
constructor.
Cheers,
Nick.
--
Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia
---------------------------------------------------------------
http://boredomandlaziness.blogspot.com
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
