On Fri, Jul 10, 2015 at 2:45 AM, Boris Zbarsky <bzbar...@mit.edu> wrote: > On 7/9/15 4:48 AM, Tim Guan-tin Chien wrote: >> >> In this case, I modified the manifest object passed from mozApp API, >> and the object was subsequently removed by the platform, so did my >> modifications. Fabrice said I should not be modified the object since >> it's marked as read only in WebIDL. > > > "readonly" just means the property has a getter but no setter. Whether you > can then modify the value returned by the getter is a separate issue that > needs to be considered as part of designing an API. > >> I wonder if platform should >> protect web authors more by simply freeze the entire structure when >> giving it to the content. > > > If it were a dictionary, you could use > <https://developer.mozilla.org/en-US/docs/Mozilla/WebIDL_bindings#Frozen>. > But note that freezing is not recursive, so if some of the properties are > themselves objects _they_ could still be mutated... > >> Are there any other APIs expose a structure like this? > > > Looks like we only use [Frozen] on sequences at the moment... > > -Boris
Thanks for reply :bz. In that case, the right question to ask would be (A) should DOMApplication#manifest be a recursive frozen JS structure, and maybe (B) should WebIDL binding provide an keyword like DeepFrozen that could recursive freeze the exposed structure. In essence, (A) is the API design question, (B) is the infrastructure needed should answer to (A) is an yes. I would personally vote yes on both (A) and (B). Tim _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
