# proposal extensions (Was: Re: Sep 26 meeting notes)

Sean Eagan seaneagan1 at gmail.com
Thu Sep 29 14:07:48 PDT 2011

On Thu, Sep 29, 2011 at 3:30 PM, Brendan Eich <brendan at mozilla.com> wrote:

> The idea is that sealing an object is more common than freezing it, while freezing a property is more common than sealing it.

I was thinking freezing an object is more common than sealing, but #
for freeze, ## for seal looks backwards anyways.

> We don't want # as a prefix for value types.

Agree, but why not for at least Arrays if not Functions and Regexps as well ?

Probably shouldn't have <| for value types either then right ?

>> Compose with <|:
>> null <| ##{...} // record-esque
>> null <| ##[...] // tuple-esque
> These are too long if common, they want the HoMD single # prefixing.

Agree.  I think composition with <| still is needed though for
consistency with non-#-prefixed literals if nothing else.

>> Include tuple-isms for #[], ##[]:
>> holes => syntax error
>> length cannot be greater than 2^32 - 1
> Sure, this carries over for all tuple proposals (I assert). But we want shorter syntax, no doubled funny chars, no verbose regularity at the expense of common cases being relatively overlong.

So if #[] is added as shorthand for a sealed Array, do you agree that
#[0,,1] should be a syntax error ?

Sean Eagan

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