It crossed my mind, but it looks like a lot of magic. TeX runs Perl which compiles and runs C... I'll try a tiny example, thanks.

Unfortunatelly, I have problems with using Inline in PerlTeX.

Here's a little LaTeX code I wrote to test the concept:

\documentclass{article}
\usepackage{perltex}
\perldo{
    `rm -rf ./_Inline && mkdir ./_Inline`;
    use Inline Config => DIRECTORY => './_Inline/';
}

\perlnewcommand{\compilec}[1]{
    {
        my $cc = "void just_compile() { $_[0] };";
        Inline->bind(C => $cc);
        just_compile();
        "";
    }
}

\begin{document}

\compilec{1 + 1;}

\end{document}
[download]

It works fine, i.e. the code compiles. However, when I change the expression to something invalid, e.g.:

\compilec{1 + nonexisting;}
[download]

TeX spits no errors and just hangs at 100% CPU for both Perl and Tex.

Running the corresponding "clean" Perl code outside PerlTeX and looking I see it dies:

/home/jest/perl/perl-5.10.1/bin/perl /home/jest/perl/perl-5.10.1/lib/s
+ite_perl/5.10.1/ExtUtils/xsubpp  -typemap /home/jest/perl/perl-5.10.1
+/lib/5.10.1/ExtUtils/typemap   perltext1_pl_f7f6.xs > perltext1_pl_f7
+f6.xsc && mv perltext1_pl_f7f6.xsc perltext1_pl_f7f6.c
cc -c  -I/home/jest/temp/t -D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-st
+rict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFI
+LE_SOURCE -D_FILE_OFFSET_BITS=64 -O2   -DVERSION=\"0.00\" -DXS_VERSIO
+N=\"0.00\" -fPIC "-I/home/jest/perl/perl-5.10.1/lib/5.10.1/i486-linux
+-gnu-thread-multi/CORE"   perltext1_pl_f7f6.c
perltext1_pl_f7f6.xs: In function ‘just_compile’:
perltext1_pl_f7f6.xs:5: error: ‘bla’ undeclared (first use in this fun
+ction)
perltext1_pl_f7f6.xs:5: error: (Each undeclared identifier is reported
+ only once
perltext1_pl_f7f6.xs:5: error: for each function it appears in.)
make: *** [perltext1_pl_f7f6.o] Error 1

A problem was encountered while attempting to compile and install your
+ Inline
C code. The command that failed was:
  make > out.make 2>&1

The build directory was:
/home/jest/temp/t/_Inline/build/perltext1_pl_f7f6

To debug the problem, cd to the build directory, and inspect the outpu
+t files.

 at perltext1.pl line 8
[download]

BTW, PerlTeX handles normal die-s just fine; but in this case it can't handle errors.

I contacted Scott Pakin, author of PerlTeX. He corrected the program to be more robust under complicated environments, like Inline::C. It will soon hit CTAN. I checked the corrected PerlTeX, works with the above example just fine!

However, I was in a (time-constrained) need to parse the mentioned structures, so I wrote a little module of my own, Data::Typed::Expression. The very early version should be on CPAN soon.