1048636 - Deprecate legacy comprehension expressions

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Shu-yu Guo [:shu]]

Parsing these is stuff of nightmares. And since these will never be standardized, we should remove them eventually. Start by deprecating.

Comment 1

[Shu-yu Guo [:shu]]

Attachment: Deprecate legacy generator expressions.

Comment 2

[Jeff Walden [:Waldo]]

Comment on attachment 8471243 [details] [diff] [review]
Deprecate legacy generator expressions.

Review of attachment 8471243 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/js.msg
@@ +441,5 @@
>  MSG_DEF(JSMSG_PROXY_CONSTRUCT_OBJECT,   387, 0, JSEXN_TYPEERR, "proxy [[Construct]] must return an object")
>  MSG_DEF(JSMSG_PROXY_GETOWN_OBJORUNDEF,  388, 0, JSEXN_TYPEERR, "proxy [[GetOwnProperty]] must return an object or undefined")
>  MSG_DEF(JSMSG_CANT_REPORT_C_AS_NC,      389, 0, JSEXN_TYPEERR, "proxy can't report existing configurable property as non-configurable")
>  MSG_DEF(JSMSG_COMP_PROP_UNTERM_EXPR,    390, 0, JSEXN_SYNTAXERR, "missing ] in computed property name")
> +MSG_DEF(JSMSG_DEPRECATED_GENEXPR,       391, 0, JSEXN_SYNTAXERR, "parenthesized generator expressions are deprecated; use yield instead")

Hmm, "use yield instead" rather under-describes it.  And this whole ES6 removing generators thing makes for even more sadfaces in what to say.  I dunno, this is horrible, but I spent too long reviewing another patch today, not going to distract myself by this badness now.  Someone more motivated can offer a better suggestion.

Comment 3

[Jason Orendorff [:jorendorff]]

Comment on attachment 8471243 [details] [diff] [review]
Deprecate legacy generator expressions.

Review of attachment 8471243 [details] [diff] [review]:
-----------------------------------------------------------------

"use ES6 generators instead"

Comment 4

[André Bargull [:anba]]

Legacy generator comprehensions were removed in bug 1220564, resolving as Won't Fix.