[XeTeX] TECkit map for Latin alphabet to Unicode IPA

[Andy Lin]

Sorry, I'm a little sleep deprived so there isn't much academic rigor
in this response.
This is the relevant portion of xunicode, which deals with the exact
definition of the \textipa command
\DeclareRobustCommand{\implementTIPAtext}{%
 \bgroup
  \let\stone\TIPAstonebar
  \let\tone\TIPAtonebar
  \setTIPAcatcodes\activatetipa
  \csname useTIPAfont\endcsname
  \implementTIPAtextx
}
\def\implementTIPAtextx#1{#1\egroup}
\def\implementTIPAtextxx#1{\endlinechar=-1 \scantokens{#1}\egroup}
\AtBeginDocument{\let\textipa\implementTIPAtext}
\expandafter\ifx\csname scantokens\endcsname\relax
\else
 \AtBeginDocument{\@ifpackageloaded{linguex}{%
  \let\implementTIPAtextx\implementTIPAtextxx}}
\fi

Theoretically, you could add the following lines to your document to
add the textipaEnvironment. But I haven't tested it. And it's longer
than it needs to be.

\expandafter\ifx\csname scantokens\endcsname%
\newenvironment{textipaEnvironment}%
{\bgroup
  \let\stone\TIPAstonebar
  \let\tone\TIPAtonebar
  \setTIPAcatcodes\activatetipa
  \csname useTIPAfont\endcsname}%
{\egroup}
\else
 \AtBeginDocument{\@ifpackageloaded{linguex}{%
   \newenvironment{textipaEnvironment}%
   {\bgroup
    \let\stone\TIPAstonebar
    \let\tone\TIPAtonebar
    \setTIPAcatcodes\activatetipa
    \csname useTIPAfont\endcsname
    \endlinechar=-1 \scantokens}%
   {\egroup}}}
\fi

Hope this helps,
Andy