Hi,

I'm trying to define concise biblatex-style citation macros for a custom
bibliographic style specification with support for intelligent placement of
trailing punctuation, and I've encountered an unusual error. If I try to
define the macros within the btxrenderingdefinitions environment, then the
code for handling trailing punctuation with the \doifinstring and
\doifnotinstring macros fails in some cases. Specifically, it correctly
detects when the trailing punctuation is a period, comma, or semicolon, but
not when it is a colon, exclamation point, or question mark. The following
MWE reproduces the error:

```

\startbtxrenderingdefinitions[myspec]

\def\autopuncttest#1#2{%

\removeunwantedspaces%

\doifinstring{#2}{,.!?;:}{#2}%

\footnote{#1}%

\doifnotinstring{#2}{,.!?;:}{#2}%

}

\stopbtxrenderingdefinitions


\usebtxdefinitions[myspec]


\starttext

This works \autopuncttest{Footnote 1}, as does this \autopuncttest{Footnote
2}; and so does this \autopuncttest{Footnote 3}.\blank

But this one fails if defined in the bib spec \autopuncttest{Footnote
4}!\blank

And why does this one fail in the bib spec too \autopuncttest{Footnote
5}?\blank

\stoptext
```

Everything works as expected if the macro definition is outside of the
btxrenderingdefinitions
environment. But within the environment, do certain punctuation marks need
to be escaped in the second argument of \doifinstring? Or is this a bug?

Joey