We can't print function pointer addresses at all, since converting
a function pointer to a void* is forbidden with ANSI C, so we only
print the function name.
Revert 'add context and flag argument to js_newstate' commit.
The context argument just adds clutter. The flag which was intended
for JS_DEBUG and/or JS_STRICT shouldn't be necessary.
js_newcfunction and js_newcconstructor need an extra argument, the
name of the function to use in stack traces.
Separate literal/interned and garbage collected string types in js_Value.
js_pushintern/js_tointern are convenience functions to push/pop strings and
automatically intern them (so that the string pointers are guaranteed to be
stable).
js_pushliteral should push stable strings (either interned or actual literals).
js_pushstring will copy the string into garbage collected memory.
The pointer returned by js_tostring is guaranteed to be stable only for as long as
the stack slot it came from remains untouched.
Some uses will always cause a string to be interned:
* Using it as a property name.
* Wrapping it in a new String() object.
* Strings returned by toString().
ToPrimitive must not clobber the stack, so the result has to be unrooted.
* Numbers converted to strings (by js_tostring)
Likewise, we have nowhere to store the temporary string here.
Passing in a scratch buffer to js_tostring could help this problem.
Mostly an issue with array accesses (OP_GETPROP, etc) so an auxiliary
function and we don't have to clutter the API needlessly.
When a function does not use eval, arguments, with and has no inner
functions it does not need a closure. We can call it without creating
a variable object if we store local variables on the stack instead.
Good style for Javascript advocates opening braces on the same line,
because there is less danger of intersecting badly with automatic
semicolon insertion.
js_newuserdata(J, tag, ptr) creates a userdata object, wrapping the ptr.
It takes the prototype for the new object from the top of the stack, just
like js_newcconstructor does.
js_touserdata(J, tag, idx) extracts the userdata pointer. Throws a
TypeError if the object is not a userdata object with a matching tag.
js_isuserdata(J, tag, idx) checks if a value on the stack is a userdata
object with a matching tag.
