dvm—dynamic virtual machine
Add propper error handling to assembler


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            -*- dvm: dynamic virtual machine -*-

dvm is a virtual machine for a high level, dynamically typed,
prototype based language. Everything in dvm programs is an
object, similar to a lua or javascript object. Keys to objects
can be any dvm type, and the special key `proto$` refers to
the object's prototype. 

Objects are passed by reference and are garbage collected.
Functions are also objects whose prototype is the global
object `function`. The global (root) object in dvm programs
is called `$`. All variables and functions are entries in
this object. A copy of the global state can be made by creating
an object with it as it's prototype.

The basic (non-object) value types in dvm are as follows:
- number: a 64 bit float, dvm does not have integer values
- byte: one byte
More may be added as development progresses.

Strings are constructed as arrays of runes. They are reference
types, but they cannot be added to in place.

Lists are just objects that tend to use numeric keys. There is
no specific list type.

  Note: Lists may be represented as vectors under the hood for
  performance reasons.


dvm's assembly language looks fairly similar to most other
assembly languages. Here is an example

  ; $ refers to the global object
  ; @ refers to the function's owner. Used to set an object's
  ;   properties in a member function. If the function belongs
  ;   to the object's prototype, @something will refer to the
  ;   prototype instance of something if something does not
  ;   exist on the object itself, however, attempting to set
  ;   the value of something will always refer to the object
  ;   itself, not it's prototype.
  ; % refers to a functions local variables. These can only
  ;   be numbers for performance reasons.

  ; set global `num` to 24
  $num = 24
    push $num
    push 2
    %1 = new $squarer
    pop %1.num
    ; the method to invoke
    push %1.square
    ; the object to invoke it on
    push %1
    ; invoke the top item item on the stack with no arguments

  ; new is syntactic sugar for the following:
  ; $squarer = $nothing ; nothing is a global, empty object.
  ; $squarer.proto$ = $object
  $squarer = new $object
    push @num
    push $print
    push $


Run the usual commands to build dvm. In addition, libcollect
is required to be installed. Download and build it from
<github.com/swissChili/libcollect>. The configure script will
require that the .pc and .so files are installed in a standard
location like /usr/local.

  # build libcollect
  $ mkdir build && cd build
  $ cmake ..
  $ make
  $ sudo make install

  # build dvm
  $ ./configure
  $ make
  $ sudo make install