=head1 Administrative Issues

For all my prodding on top level parrot issues, tcl really has no
roadmap, either. If you're at all interested in working on this project,
let me know, and I'll work on clarifying.

=over 4

=item interactive tclsh

simple interactive mode now exists. 

 o Should catch any real_exceptions thrown.
 o respect tcl_prompt1, tcl_prompt2 (Depends on true global support)
 o deal with incomplete input
 o give invalid commands to the system.

=item [interpinfo name]

how to do this from inside parrot?
[ there's a RT ticket for this now, someone should put the # here.]

=item migrate all these issues to RT.

TODO tests would also suffice, where possible -- For those of you
who know tcl, this would be a great place to contribute code - tests
based on the latest Tcl man pages will *really* help.

=item update docs/* 

=item add pod to all .imc

=back

=head1 Programming Issues

=head2 C-level tasks

=over 4

=item List to String

The current list to string logic in C<dynclasses/tcllist.pmc> is missing logic
to properly escape string elements.

=item string to list 

Should be moved to tcllist's set_string method.

=item tclword

An object is probably too heavyweight for this. A PMC with a few overloaded
methods is probably sufficient.

=item Use PMCs to handle numifying

not the pir routines we now have. Verify that [expr 2a + 2b] behaves
appropriately when doing this. Include proper numification of octal and
hex.

=back

=head2 PIR-level tasks

=over 4

=item globals vs. lexicals

Right now, globals are done with lexicals. get_var/set_var needs to be 
updated to check the call_level - if we're at 0, then use a global. [global]
and [upvar] will need attention once this is done.

=item implement default globals, etc.

global variables provided by tcl libary. L<tclvars>.

global variables provided by tcl interpreter. L<tclsh>

source per-user settings. L<tclsh>

=item misc

hex & unicode escapes are not currently supported in 
C<dynclasses/tclparser.pmc>'s C<parse>. - I have a version of this in my
sandbox, but it requires more work from parrot guts.

=item unimplemented commands/subcommands 

[after] [array get] [array names] [array unset] 
[array statistics] [array anymore] [array donesearch]
[array nextelement] [array startsearch] [bgerror] [binary] 
[case] [clock] [close] [cd] [dde] [encoding] [eof] [exec]
[fblocked] [fconfigure] [fcopy] [file] [fileevent]
[flush] [gets] [glob] [http] [info] [interp] [library]
[lindex] [load] [lreplace] [lsearch] [lset] [lsort] 
[memory] [msgcat] [namespace] [open] [package] [pid] [pwd]
[read] [registry] [regexp] [regsub] [resource] 
[safe] [scan] [seek] [socket] [subst]
[string replace] [string tolower] [string totitle] [string toupper]
[string trim] [string trimleft] [string trimright]
[string compare] [string equal] [string last]
[string bytelength] [string is] [string map]
[string wordstart] [string wordend] [switch] [tcltest]
[tell] [update] [variable] [vwait]

=back

=head2 Tests

=over 4

=item standards

Any future tests, write more like t/tcl_var_subst.t. Eventually cleanup
tests so they're consistent.

=item Add tests for...

tclword.imc, PMCs, the macros, expr's precedence and parens,
[puts]'s ability to write to other channels, the C<compreg> compiler.

[uplevel] [upvar] [lrange] [inline] [string repeat] 

=item pass any test in the tcl test suite ^_^

=back

=head1 Uncategorized Issues

=over 4

=item Remove Perl*

Mostly done. All that seems to be left is PerlUndef. Much was already
converted to the internal types. PerlUndef removal will probably result
(finally) in the use of null checks where it's being used for that, and
TclObject where it's being used for shimmering.

Left in:

./lib/commands/inline.imc
./lib/commands/open.imc
./lib/commands/source.imc
./lib/expression.imc
./lib/get_var.imc
./lib/tclword.imc

=item tail call optimizations

tail call optimizations - there are several cases where I could use this
and save myself a call. Possible to do right now with PASM - wait for
PIR support before welding in.

=item provide a way to access existing library PIR from Tcl.

=item TclWord

implement C<is_const> to allow for some optimizations in the compiler. 
(which isn't written yet.)
when adding words, default to true, but if at any point we add a variable
or a command, invalidate that. (mostly done!)

Move TclWord namespace into _Tcl::Word, less clutter?

=item multiple level lists

=item compiler vs. interpreter

it should be possible to further extend our interpreter
this to make an actual compiler, where the compiler emits PIR. 

And once we have the pir_code, we can either emit the necessary
PIR (ala parrot's -o option) or we can compile and run it.

Caveat: how to support -o with user defined procs - right now, proc is defining
the sub on the fly, where, with a compiler, we may want to defer compilation,
and simply be able to extract the generated PIR.

=item expr

Clean up [expr]. MUUUUCH room for improvement there. [expr] is the source
of most of our abysmal performance in bench.tcl.

the expr AST could use a rework. Be nice if it just passed around something
invokable.

clean up expr so that it's not passing around
type indicators. - just use PMCs everywhere. (Though we may still need
to have CONST vs. VARIABLE types.)

The type indicator is also used to disambiguate operators and function calls
from operands. We can easily remove it for operands, but how to cleanly
remove this for operators? 

TBD: strings, floats as operands - (many of the math funcs return floats
but you can't specify them, and not everything takes them 
(try, for example, [expr sin(1) + sin(1)] vs [expr sin(1) * sin(1)].)

TBD: blocks, commands, and strings as operands

TBD: logical binary ops & ternary op (need deferred evaluation) ; unary ops;
ops that work on strings only.

TBD: functions that take > 1 arg.

TBD: Argument type requirements - Currently works ONLY on bitand - esp need
to get any that require int-only args, as we can now /generate/ floats,
even if we cannot specify them. This is all supportable by MMD - we just
need to specify the correct errors to throw.

=item misc

complete [error] (need global var support)

=back

=cut
