Re: string:sub

[joao lobato <btnfdp.lobato@...>]

On 3/6/10, Roberto Ierusalimschy <roberto@inf.puc-rio.br> wrote:
>> If s:sub(5,4) is valid then s:sub(1,0) should be valid too.
>
> Sure. s:sub(1,n) is the prefix of 's' with length 'n', so zero must be
> a valid index to allow the empty prefix. zero is not negative, so it
> counts from the beginning.
>
> -- Roberto
>

It's just that since s:sub(2,n) doesn't mean "the substring of 's'
with length 'n' starting at the second position of 's'", it just feels
that your point is a happy coincidence rather than a particular case
of a rule.

I feel like I managed to misuse the "principle of [Roberto's] least
surprise" and break list etiquette.