Extend API to allow setting length property for function templates.

Extend API to allow setting length property for function templates.

R=yangguo@chromium.org
BUG=125308
Committed: http://code.google.com/p/v8/source/detail?r=13240

[Yang, 2012-12-19 09:14:45]

LGTM with one suggestion.

https://codereview.chromium.org/11631002/diff/1/src/api.cc
File src/api.cc (right):

https://codereview.chromium.org/11631002/diff/1/src/api.cc#newcode1073
src/api.cc:1073: obj->set_length(0);
We have this Signature object (third argument in this New-method) where we can
specify the number of arguments. In our repo the Signature object is only used
in test-api.cc, but maybe it makes sense to set the length to the argc (length
of the arg-FixedArray) in Signature?

[rossberg, 2012-12-19 10:21:50]

https://codereview.chromium.org/11631002/diff/1/src/api.cc
File src/api.cc (right):

https://codereview.chromium.org/11631002/diff/1/src/api.cc#newcode1073
src/api.cc:1073: obj->set_length(0);
On 2012/12/19 09:14:45, Yang wrote:
> We have this Signature object (third argument in this New-method) where we can
> specify the number of arguments. In our repo the Signature object is only used
> in test-api.cc, but maybe it makes sense to set the length to the argc (length
> of the arg-FixedArray) in Signature?

Interesting idea. But as discussed offline, it's probably preferable to keep
internal type checking (which is what Signature supports) and the rather
arbitrary value of the 'length' property separate concerns.

I added length as an additional optional argument to the New constructor,
though.

[Yang, 2012-12-19 10:26:04]

On 2012/12/19 10:21:50, rossberg wrote:
> https://codereview.chromium.org/11631002/diff/1/src/api.cc
> File src/api.cc (right):
> 
> https://codereview.chromium.org/11631002/diff/1/src/api.cc#newcode1073
> src/api.cc:1073: obj->set_length(0);
> On 2012/12/19 09:14:45, Yang wrote:
> > We have this Signature object (third argument in this New-method) where we
can
> > specify the number of arguments. In our repo the Signature object is only
used
> > in test-api.cc, but maybe it makes sense to set the length to the argc
(length
> > of the arg-FixedArray) in Signature?
> 
> Interesting idea. But as discussed offline, it's probably preferable to keep
> internal type checking (which is what Signature supports) and the rather
> arbitrary value of the 'length' property separate concerns.
> 
> I added length as an additional optional argument to the New constructor,
> though.

LGTM.