Garrett Smith wrote: > It seems that the > documentation is very unclear and that is the source of the confusion. > > The 3.1 draft defines [[Flexible]] as a property attribute:- > > | [[Flexible]] boolean If true, attempts to delete the > | property or change its attributes will succeed. Otherwise, > | the property is said to be sealed. See the description of the > | delete operator in section 11.4.1, and the reflective Object > | methods . > > That definition of [[Flexible]] seems to imply: > > 1) true - property can be deleted using - delete - operator. > 2) false - property is sealed. What is sealed?
You missed a very important part: "or change its attributes". [[Flexible]] affects what you can do with a property and its attributes. It will feel more concrete if you change the word order: ,------- | [[Flexible]] boolean If true, attempts to change the attributes | of the property, or to delete the property, will succeed. `------- Ignore "sealed", that word adds confusion. [[Flexible]] is not about an object as a whole. There's a more informative description on page 9 of the PDF document that is linked to here: https://mail.mozilla.org/pipermail/es-discuss/2008-July/006664.html Quoting from there, the following text talks about what this attribute affects: ,------- | In ES3 the possible basic state transitions of a property are | to create the property, to change the value of the property, | and to delete the property. The ES3 ReadOnly and DontDelete | property attributes regulate the ability make the latter two | transitions. With the addition of getter/setter properties | and reified property attributes, there are additional possible | property state transitions such as replacing a getter or setter | function, changing an attribute of a property, changing a data | property into a getter/setter property, and changing a getter/setter | property into a data property. `------- I hope this helps. -- Ingvar von Schoultz _______________________________________________ Es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
