Expandable \doifelse tests

Expandable \doifelse tests

[Henri Menke]

Dear list,

Motivated by this question on TeX.SX https://tex.stackexchange.com/questions/370868 I was fiddling around with the \doifelse conditionals.  I noticed that most of them are not expandable, which makes it very difficult to concatenate them.  Here a simple example

\starttext

\doifelse{a}{%
  \doifelse{x}{x}{a}{b}% <- evaluates to "a" but not expandable
  }{yes}{no}

\stoptext

This outputs "no" even though "a" is equal to "a".

Would it be possible to substitute these conditionals by expandable ones?  I would volunteer to help make them expandable.

Cheers, Henri
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Re: Expandable \doifelse tests

[Wolfgang Schuster]

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\starttext

\expdoifelse{a}{\expdoifelse{x}{x}{a}{b}}
   {yes}
   {no}

\stoptext

Wolfgang

> Henri Menke <mailto:henrimenke@gmail.com>
> 21. Mai 2017 um 10:14
> Dear list,
>
> Motivated by this question on TeX.SX 
> https://tex.stackexchange.com/questions/370868 I was fiddling around 
> with the \doifelse conditionals. I noticed that most of them are not 
> expandable, which makes it very difficult to concatenate them. Here a 
> simple example
>
> \starttext
>
> \doifelse{a}{%
> \doifelse{x}{x}{a}{b}% <- evaluates to "a" but not expandable
> }{yes}{no}
>
> \stoptext
>
> This outputs "no" even though "a" is equal to "a".
>
> Would it be possible to substitute these conditionals by expandable 
> ones? I would volunteer to help make them expandable.
>
> Cheers, Henri
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry 
> to the Wiki!
>
> maillist : ntg-context@ntg.nl / 
> http://www.ntg.nl/mailman/listinfo/ntg-context
> webpage : http://www.pragma-ade.nl / http://context.aanhet.net
> archive : https://bitbucket.org/phg/context-mirror/commits/
> wiki : http://contextgarden.net
> ___________________________________________________________________________________


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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

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wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Expandable \doifelse tests

[Meer, Hans van der]

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While going through the posts I had stowed away because I found them interesting, I came along this one.
There is not a problem here, just a tiny observation.

In order to work
   \doifelse{a}{\doifelse{x}{x}{a}{b}}{yes}{no}
properly it is sufficient that the inner \doifelse is of the expandable kind.

Thus
   \doifelse{a}{\expdoifelse{x}{x}{a}{b}}{yes}{no}
yields the same as
  \expdoifelse{a}{\expdoifelse{x}{x}{a}{b}}{yes}{no}

Hans van der Meer




On 21 May 2017, at 10:21, Wolfgang Schuster <schuster.wolfgang@gmail.com<mailto:schuster.wolfgang@gmail.com>> wrote:

\starttext

\expdoifelse{a}{\expdoifelse{x}{x}{a}{b}}
  {yes}
  {no}

\stoptext

Wolfgang

Henri Menke<mailto:henrimenke@gmail.com>
21. Mai 2017 um 10:14
Dear list,

Motivated by this question on TeX.SX https://tex.stackexchange.com/questions/370868 I was fiddling around with the \doifelse conditionals. I noticed that most of them are not expandable, which makes it very difficult to concatenate them. Here a simple example

\starttext

\doifelse{a}{%
\doifelse{x}{x}{a}{b}% <- evaluates to "a" but not expandable
}{yes}{no}

\stoptext

This outputs "no" even though "a" is equal to "a".

Would it be possible to substitute these conditionals by expandable ones? I would volunteer to help make them expandable.

Cheers, Henri
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl<mailto:ntg-context@ntg.nl> / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl<http://www.pragma-ade.nl/> / http://context.aanhet.net<http://context.aanhet.net/>
archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net<http://contextgarden.net/>
___________________________________________________________________________________

___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl<mailto:ntg-context@ntg.nl> / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________


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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________