On Mon, May 4, 2009 at 10:26 PM, Brendan Eich <[email protected]> wrote:
> ??= and ?? are too narrowly typed for JS. I had the impression from the previous thread that you were more in favor of ??= than ||=. People often write the following at the beginning of functions for optional parameters optionalParam = optionalParam || defaultVal; I believe what they are really trying to write is optionalParam = optionalParam === undefined ? defaultValue : optionalParam; which is what ??= would do. I think optional parameters are the nuisance use case that is fueling any discussion about a ||= or ??= operator. I think other use cases are less common and probably would not warrant adding a new operator. The reason I mention this is if there is another sugar plan for default parameter values then perhaps ||= and ??= aren't needed at all (though I think they are probably worth adding.) I thought default parameters were going to be something like the following. function(a=1, b="defaultVal"); And in this syntax will default values be used if the parameter is falsey or only if it is undefined? Peter _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
