use "" as an array key

[Peter TB Brett]

On 24/09/2016 04:26, Kay C Lan wrote:
> On Fri, Sep 23, 2016 at 2:27 AM, Peter TB Brett
> <peter.brett at livecode.com> wrote:
>>
>> "" isn't "the absence of a string", it's a string that's 0 characters long.
>> Being able to use it as an array key is important for being able to
>> represent real-world data in an array.
>
> It's an important point that "", a 0 character string is not the same
> as NULL because we as humans often 'see them' as the same.

Very confusingly, "null" in LiveCode Script is _not_ the same as "NULL" 
in SQL.

In LiveCode, "null" is shorthand for "numtochar(0)".

LiveCode Script doesn't really have the concept of "no value at all" 
that is modelled by SQL's "NULL".  Most of the syntax fakes it by using 
the empty string, but unfortunately that doesn't work everywhere.

LiveCode Builder has "nothing", which is a proper "no value".

                                   Peter

-- 
Dr Peter Brett <peter.brett at livecode.com>
LiveCode Technical Project Manager

lcb-mode for Emacs: https://github.com/peter-b/lcb-mode