tinkering with parsers
added brace-ized expression lists
changed parse function to call expressionList
now with an AST
assignment and single-char symbol tokenize/parse
some symbol table data type stuff
threaded symbol table through evaluate. maybe this could be cleaned up with functors?
ternary operator and repeat
wrapping head (biological) around State monad
adding to state derivation exercise
do and put written out explicitly in state explorations
partial work on parsing built-ins correctly according to arity
evaluator now uses a State Monad. lifted/packed versions of unary
and binary operations in the evaluater.
cleaned up runString, evaluate ExprTreeListNode, and evaluate Repeat
to make all of them nicely monadic
temp commit
temp commit
First working output to SVG.

--   echo "#36{R10#8{F25L45}}" | runghc tinker.hs | display svg:-
--   echo "#8{R45#6{#90{F1R2}R90}}" | runghc tinker.hs | display svg:-
partial conversion to state monad for parsing
partial Defun/BoundDefun implementation
defuns implemented