From: Hans Hagen via ntg-context <ntg-context@ntg.nl>
To: mailing list for ConTeXt users <ntg-context@ntg.nl>
Cc: Hans Hagen <j.hagen@xs4all.nl>, Taco Hoekwater <taco@bittext.nl>
Subject: Re: nil from TeX to Lua
Date: Tue, 10 Aug 2021 09:59:37 +0200 [thread overview]
Message-ID: <e56c3c40-a5ce-3b36-571b-60f528d5ed4f@xs4all.nl> (raw)
In-Reply-To: <894692B1-E744-4FA1-A1FB-D3CA9EADD93D@bittext.nl>
On 8/10/2021 9:23 AM, Taco Hoekwater via ntg-context wrote:
>
>
>> On 9 Aug 2021, at 22:05, Aditya Mahajan via ntg-context <ntg-context@ntg.nl> wrote:
>>
>> On Mon, 9 Aug 2021, Hans van der Meer via ntg-context wrote:
>>
>>> In the TeX to Lua interface with
>>>
>>> \def\Macro#1{\directlua{luafunction("#1")}}
>>>
>>> the transfer from TeX to Lua is by string. However what to do at the Lua end when calling \Macro{}?
>>> As I understand it, then on the Lua side an empty argument and an empty string are indistinguishable.
>>
>
> On the TeX side, these are always indistinguishable (as TeX doesn’t have ’strings’) so depending
> on the called macro, you could just assume str == "” actually means nil?
indeed, just check for ""
Hans
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prev parent reply other threads:[~2021-08-10 7:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-09 19:58 Hans van der Meer via ntg-context
2021-08-09 20:05 ` Aditya Mahajan via ntg-context
2021-08-10 7:23 ` Taco Hoekwater via ntg-context
2021-08-10 7:59 ` Hans Hagen via ntg-context [this message]
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