Allow a separate getter/setter attribute pair

[saschanaz]

What problem are you trying to solve?

Trusted Types added a bunch of IDL changes like this:

[CEReactions] attribute (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;

This is to assign TrustedHTML object, while the getter will only ever return a DOMString. The intention is not clear from the IDL until you read the prose.

What solutions exist today?

Just use the most permissive type to allow both getter and setter requirements 😞

How would you solve it?

Something like the following would be nicer:

attribute getter DOMString innerHTML;
[CEReactions] attribute setter (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;

Although the syntax is sad - it allows invalid setup like having a setter only.

[CEReactions, GetterType=DOMString]
attribute (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;

Something like this could work too, but I'm not very happy to put types into extended attribute value 🤔

Anything else?

Found while reading the result of microsoft/TypeScript-DOM-lib-generator#2074.

[domenic]

I've wanted better getter/setter syntax for some time. #485 has some previous discussion. This issue points to some concrete benefits that might bring.

Since that issue, class accessor syntax has been proposed for JS. (And even reached stage 3, although it's stuck since no implementers seem to be interested in implementing...)

My proposed syntax would be something like

get DOMString innerHTML;
[CEReactions] set (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;

accessor DOMString textContent;