Re: Lua Suggestion: return nil in string.find/match() for indexes that are before the string

[Coroutines <coroutines@...>]

On Sun, Mar 2, 2014 at 12:18 AM, Dirk Laurie <dirk.laurie@gmail.com> wrote:
> 2014-03-02 9:06 GMT+02:00 Coroutines <coroutines@gmail.com>:
>
>> This does not:
>>
>>> = string.find('cat', 'cat', -31, true)
>> 1 3
>
>> I expect it to match the string at the index I passed to it, not
>> silently reposition the start at a valid index (1).
>
> All the string functions do that. It is documented under string.sub.
>
> | If, after the translation of negative indices, i is less than 1, it
> is corrected to 1.
>

Yes :-)  I believe it makes sense for string.sub(), as you would want
the valid portion of the string from (let's say) -31 to 5.  This would
be readjusted to only "sub out" indexes 1 through 5.  I do not believe
it makes sense for string.find()/string.match() -- as false-positives
are possible when I tell it to match somewhere clearly before the
string (in a place it doesn't exist).