On Jun 11, 2009, at 9:59 AM, Toshiyasu Morita wrote:
--- On Wed, 6/10/09, Gavin Barraclough <barraclo...@apple.com> wrote:
> If you consider calling a JS function with too few arguments as
being akin to =
> invoking a C++ method with some defaulted parameters not-provided,
then it is
> also the responsibility of code generated for the call to such a
method to ensure
> that values for all declared parameters are passed.)
Thanks for the long explanation.
Can the arity check be performed at compile time as in C++?
Toshi
Alas no because you can't really guarantee exactly what function will
be called (except in a few relatively uncommon cases), eg.
function g() {
for (var i = 0; i < 100; i++)
f(a*i);
}
g();
So if we look at the call to f(a*i) we need to ask "what is the arity
of f?", so the issues we need to deal with to answer this question
statically are
* the object f may not be defined or it may not be a function at
compile time -- at runtime f may have become a function, or it may not
* any function call may result in f being changed and function calls
may occur during arithmetic if you cannot guarantee the input types
These two things together mean it's not reasonably possible to
guarantee the same function will be called every time, let alone have
the same arity.
--Oliver
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