After you two's discussion, I have some understanding about lexical scope
and dynamic scope. I will add lexical binding if my code use it.

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On Mon, Jun 19, 2017 at 6:37 PM, Bastien Guerry <bzg@gnu.org> wrote:

> Hi Nicolas,
>
> I'm all for lexical-binding, and it's good to have it in Org's core.
>
> The author of ob-sclang.el used "2011-2017" for the copyright years,
> which was obviously a typo and tells that the header was simply copied
> from another file (which is 100% fine btw).
>
> From that, I inferred that the "lexical-binding:t" was also copied
> without further thinking, especially since there is no binding at all
> in this file.
>
> I think Stardiviner is the one who should make the decision, but I
> don't see what "lexical-binding:t" would add to his actual code.
>
> For the more general concern: again, I'm all for lexical binding and
> I'm well aware of its numerous advantages, but I don't think we should
> rule dynamic binding from contributed Org code.  Dynamic binding has
> it's limitations, but when used carefully, it also has the advantage
> of being easier to grok for beginners.  We want to welcome beginner's
> contributions.  So I simply recommand lexical binding for Org's core,
> and what fits developers best for Org's contributions.
>
> And I agree we can move on to something else :)
>
> --
>  Bastien
>