Another Wart! string.find() [ was: namespace issue? ]

[Andrew Dalke]

Steven D. Majewski wrote:
>  It probably *ought* to return None for not found:
>     "string"[None] yields an exception:
>     "TypeError: sequence index must be integer"
>      while "string"[-1] returns "g"
>   so a coding error is likely to slip thru without an exception.
 ...
>  I'ld love to see it fixed, however, I suspect that in this case,
>  many lines of installed code trumps Computer Programming for Everybody!


>>> print string.find.__doc__
find(s, sub [,start [,end]]) -> in

Return the lowest index in s where substring sub is found,
such that sub is contained within s[start,end].  Optional
arguments start and end are interpreted as in slice notation.

Return -1 on failure.
>>> print string.index.__doc__
index(s, sub [,start [,end]]) -> int

 Return the lowest index in s where substring sub is found,
 such that sub is contained within s[start,end].  Optional
 arguments start and end are interpreted as in slice notation.

 Raise ValueError if not found.


>>>

Only difference is what to do when the substring isn't found;
return -1 or raise a ValueError.

                    Andrew
                    dalke at acm.org