string.byte returning nothing (Re: Changelog for 5 - 3/3/2003)

[Dimiter 'malkia' Stanev <malkia@...>]

Bringing this one out of the dead.

At some point it was considered that string.byte would return nil 
instead of nothing. For example type((''):byte()) bombs now.

> - string.byte returns nil for index out-of-range

What was the consensus for keeping the current implementation.
I'm just curious. It's just a matter of better learning for me.

For example:

local a,b,c=(''):byte(),1,2
print(a,b,c)
# nil 1 2

I would've thought this should be

# 1 2 nil

P.S. There is one more peculiarity:

# Note the coma at the end
local a,b,c=('ab'):byte(1,2),
print(a,b,c)
# nil nil nil

Thanks!

On 3/3/2003 3:16 PM, Roberto Ierusalimschy wrote:
> Quick list of changes from 4.0  to 5.0:
>
> - coroutines
> - lexical scoping
> - metatables (x tags)
> - weak tables
> - generic for
> - proper tail call
> - boolean type
> - new way to handle userdata in the C API (+ light userdata)
> - new way to handle errors in the C API
> - new functions (time/date, tmpfile, unpack, require, load*, )
> - block comments  --[[...]]
> - still faster
> - better error messages
>
>
> Quick list of changes from 5.0 beta to final:
>
> - no-nonsense debug info about tail calls
> - correct implementation for comparison metamethods
> - getn/setn in lauxlib
> - two new debug functions to manipulate upvalues
> - string.byte returns nil for index out-of-range
> - "require" returns value returned by package
> - get/setglobals renamed to get/setfenv ("function environment")
>
>
> -- Roberto