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Date:         Thu, 6 Nov 2008 11:48:34 +0100
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From: =?ISO-8859-1?Q?Lars_Hellstr=F6m?= <Lars.Hellstrom@RESIDENSET.NET>
Subject: Re: Some implementation details of \let:XX
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
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Status: R

Will Robertson skrev:
> Hello,
> 
> Taking a look at how \let:NN and friends are implemented strongly 
> tempted my "clean up" urge. Rather than delay it for the "big future 
> refactor" that's going to happen at some stage, I thought it small 
> enough to address immediately.
> 
> (Also, I'm using this public list since I'm not entirely sure that 
> conducting the expl3 business "in the dark" isn't one of the reasons 
> that the project has attracted less interest than we possibly would have 
> liked.)
> 
> Here's the offending code:
> 
> \def_protected_long_new:Npn \let:NN #1{\let:NwN #1=~}
> \def_new:Npn\let:cN #1 {\exp_after:NN\let:NN\cs:w#1\cs_end:}
> \def_new:Npn\let:Nc{\exp_args:NNc\let:NN}
> \def_new:Npn\let:cc{\exp_args:Ncc\let:NN}
> 
> Yielding concerns:
>  - Why is \let:NN long?

So that it can be used on \par.

Lars Hellström