forgot to push while's body's context

fixed IAssign

consolidation of environment operations in Env module; cleanup/reorg of vm.ml; RefData takes a ref; ArrayType takes a size

more thorough automatic casting

cleaner binary operation (math) execution

syntax cleanup

break out of loops; if statements no longer add a frame

tag frames as loops or not for less hacky iteration in the vm

added a license

context extracted from while loops properly; proper exception is thrown for undeclared variables

fixed negative numbers and added a test

addition

while loops

conditionals promote condition to bool if it's not already

expression compiler returns type with instructions

branching (if statements and trinary)

updated parser test with recent AST changes (deletion of NullExpression)

updated readme

expression statements consume the value left on the stack

simple variable initialization

starting variables stuff

prefix instruction names with I

stupid change

stupid change

Several steps back, one step forward. Trying again at the compiler and vm.

move instructions to vm.ml

back to byte-code

hex numbers