- From: Brendan Eich <brendan@mozilla.org>
- Date: Tue, 11 Oct 2011 13:42:53 -0400
- To: Erik Arvidsson <arv@chromium.org>
- Cc: "Mark S. Miller" <erights@google.com>, Dominic Cooney <dominicc@google.com>, Jonas Sicking <jonas@sicking.cc>, public-script-coord@w3.org
On Oct 11, 2011, at 1:25 PM, Erik Arvidsson wrote: > Also, worth considering is optional arguments in the current ES6 > draft. In ES6 the value undefined is not treated as absent. > > function f(x = 42) { > return x; > } > > print(f()); // "42" > print(f(undefined)); // "undefined" > > So, to me it seems like the WebIDL to ES mappings needs to treat > undefined as present. Agreed. Ad-hoc argument processing in JS today may use arguments.length, or undefined testing (possibly even null-or-undefined testing via " == null"). I continue to think arguments.length is the best way for IDL. /be > > erik > > > > > > > > > On Tue, Oct 11, 2011 at 04:57, Mark S. Miller <erights@google.com> wrote: >> On Tue, Oct 11, 2011 at 8:44 AM, Dominic Cooney <dominicc@google.com> wrote: >>> >>> Since arguments.length isn't friendly to strict mode, this seems to be a >>> good assumption for the future at the very least. >> >> What's the issue with "arguments.length" in strict mode? Are you perhaps >> thinking of arguments.callee and/or arguments.caller? >> >> -- >> Cheers, >> --MarkM >> >
Received on Tuesday, 11 October 2011 17:43:23 UTC