Try it out
To try out the Tcl interpreter (called ParTcl) that is currently available with parrot: (you'll need a C compiler, make, and perl, for now.)
First, get a copy of parrot: (see http://www.parrotcode.org/source.html for instructions. You can use svn or grab a snapshot)
cd parrot perl Configure.pl make cd languages/tcl make
From here, you can cd to examples and make hello. In the tcl directory, there is also a make test target, where you can run the limited test suite. There is also a "make tcl-test" target which will grab the latest copy of the tcl test suite out of CVS; convert the tests into a something that perl's test harness can run, and then run the tests.
You can also see the PIR that your tcl compiles to with the *--pir* option. Also, you can use *-e* to specify the tcl on the command line, ala perl.
../../parrot tcl.pbc --pir -e='puts [expr 2 + 2]'
This is a tcl compiler. Code is parsed out into words, which are handed off to objects that know how to compile themselves. Once we have an object containing the parsed code, we compile it to PIR, and then compile the PIR (Parrot intermediate representation, a step or two above assembler) to parrot bytecode. A new partcl-only option --pir allows you to dump the PIR that would be executed.
Since this is a brand new implementation on parrot, it would be nice to take advantage of parrot features like the Parrot Grammar Engine (see PerlSixGrammars)
Make the compiler smart enough to know when it can no longer use cached versions of the builtins.
Pass most of tcl's test suite. With "make tcl-test", we can now run a (very slightly converted) version of the tcl suite using partcl. While at one point we did a lot of conversion to run these tests in a perl-based harness, we are now running them entirely through partcl. This is accomplished by providing a Test::More like API that has a 'test' fronted - this is shim'd into the header of each .test file, which can then be run directly by partcl. Switching to this way brings our official passing percentage down to something like 1.7% of the entire suite at the moment, but more progress is expected relatively rapidly.
Provide the ability to call routines defined in other languages from inside Tcl. (There is already a parrot standard library; eventually this would allow us to call anything, say, written in perl, using native Tcl syntax.)
Currently, the Tcl on parrot effort is being coordinated by Matt Diephouse, with some support from Will Coleda (will at coleda dot com). If you're interested in helping out, there is C, PIR, Tcl and Perl code that needs writing.