Re: Invalid order functions
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- Subject: Re: Invalid order functions
- From: Roberto Ierusalimschy <roberto@...>
- Date: Fri, 8 Feb 2008 09:39:26 -0200
> If you call table.sort with an invalid sort function, you can get a call
> with (nil) to the order function before you get the "invalid order
> function" message
>
> $ lua -e 'table.sort({1,2,3,4}, function (a,b) print(a,b) return true end)'
> 4 1
> 2 4
> 3 4
> 4 4
> 1 4
> nil 4
> lua: (command line):1: invalid order function for sorting
>
> So usually you never see the "invalid order function" error message:
>
> $ lua -e 'table.sort({1,2,3,4}, function (a,b) return a>0 end)'
> lua: (command line):1: attempt to compare number with nil
>
> Is this the intended behavior?
There is no "intended behavior" when the sort function is invalid. The
"invalid order function" error exists only to avoid a too nasty
non-intended behavior (infinite loop) in specific situations.
-- Roberto