ltnews35: reads as if IfBlankTF can be used to detect a key without a value

[Skillmon]

In the latest ltnews the subsection about \IfBlankTF reads as if it would be possible to tell key apart from key={}:

This test can also be useful if you set up key/value options and want to test if a key was specified without giving a value, vs. specifying "key= ,".

Actually that isn't possible at all with the current behaviour (and if it would it would make more sense to use the IfNoValueTF tests).

Try the following example to see that this doesn't work as hinted by ltnews:

\begin{filecontents*}{quickytesty.sty}
\ProvidesPackage{quickytesty}

\ExplSyntaxOn
\DeclareKeys
  {%
    test .code = \tl_analysis_show:n {#1}
  }
\ProcessKeyOptions\relax
\ExplSyntaxOff
\end{filecontents*}
\RequirePackage[test,test=]{quickytesty}
\stop

That produces:

The token list is empty
> .
<recently read> }

l.8 \ProcessKeyOptions\relax

?
The token list is empty
> .
<recently read> }

l.8 \ProcessKeyOptions\relax

?

[josephwright]

I will adjust here including details how this can be approached

[josephwright]

I'm going to close the issue here and log a separate one about documenting the new keyval stuff generally.