This adds:
- A global Date object (with `length` property and `now` function)
- The Date constructor (no arguments yet)
- The Date prototype (with `get*` functions)
You can now throw an expression to the nearest catcher! :^)
To support throwing arbitrary values, I added an Exception class that
sits as a wrapper around whatever is thrown. In the future it will be
a logical place to store a call stack.
You can now throw exceptions by calling Interpreter::throw_exception().
Anyone who calls ASTNode::execute() needs to check afterwards if the
Interpreter now has an exception(), and if so, stop what they're doing
and simply return.
When catching an exception, we'll first execute the CatchClause node
if present. After that, we'll execute the finalizer block if present.
This is unlikely to be completely correct, but it's a start! :^)
This function is ultimately supposed to be generic and allow any |this|
that has a length property, but for now it only works on our own Array
object type.
I'm not completely thrilled about Object::get() and Object::put() doing
special-case stuff for arrays, and we should probably come up with a
better abstraction for it.
But at least it works for now, which is really nice. :^)
Weirdly enough, the "simple-scopes" test doesn't return undefined
anymore, at first I thought the scoping was somehow broken, turns out
the interpreter doesn't consider the returned y as the last evaluated
value anymore, possibly because it's undefined (?).
This patch adds String.prototype.charAt() to demonstrate that prototype
property lookup works, and that you can call a prototype function on an
object, and it will do what you expect. :^)
This can be used to implement arbitrary functionality, callable from
JavaScript.
To make this work, I had to change the way CallExpression passes
arguments to the callee. Instead of a HashMap<String, Value>, we now
pass an ordered list of Argument { String name; Value value; }.
This patch includes a native "print(argument)" function. :^)
Now that we have the beginnings of a parser, let's take the script to
run as a command-line argument and move all the test scripts into
/home/anon/js :^)
To run a script, simply use "js":
$ js my-script.js
To get an AST dump before execution, you can use "js -A"
