[Python-Dev] Floating point -> string conversions
bac at OCF.Berkeley.EDU
Fri Nov 12 22:28:13 CET 2004
Batista, Facundo wrote:
> There's a thread in the standard list (with this very Subject) that
> talks about implicit coercing with "%d" in strings replacement.
> jfouhy posted this example:
> >>> pow(2, 31)
> >>> '%d' % 2147483647.0 # python will convert to int
> >>> '%d' % 2147483648.0 # too big for an int, so error.
> Traceback (most recent call last):
> File "<stdin>", line 1, in ?
> TypeError: int argument required
> >>> '%d' % long(2147483648.0) # but yet, no trouble accepting a
> >>> '%d' % int(2147483648.0) # and int() converts to long anyway
> I think that here's a bug, but don't know where:
I say it is in the conversion from float not trying it as a long to make it
work. I expect the conversion types in string interpolation to convert the
argument as needed to meet the conversion type. Since a float can safely be
converted to a long that is what should be done since in the eyes of Python int
Just think of how printf() handles it; it just interprets the argument as what
the conversion type says it is. I think Python should do the same.
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