On Tue, Oct 30, 2012 at 7:02 PM, Trevor Norris <[email protected]>wrote:
> To supplement what mscdex has already posted, here are two more articles: > > http://dailyjs.com/2012/10/15/preparing-for-esnext/ > https://brendaneich.com/2012/10/harmony-of-dreams-come-true/ > > You'l want to check out Set's. Enable them with `node --harmony` at > runtime. Also, v8 doesn't support Set initialization with an Array. So > you'll have to use .add() for every element. But they are about 6 times > faster than using an Object lookup. Sort of like the following: > > var the_set = new Set(); > the_array.forEach(function(i) { the_set.add(i); }); > Ugh, it's too bad v8's implementation is outdated, because the correct way to do exactly this is: var set = new Set(the_array); // creates a unique set with lookup API for free! yay! Rick > > As a side note, your syntax is incorrect. The forEach statement should > look like the following: > > the_array.forEach(function(i) { the_lookup[i] = true; }); > > > On Tuesday, October 30, 2012 2:50:25 PM UTC-7, Felipe Gasper wrote: > >> (Sorry, this is slightly OT.) >> >> var the_array = ["foo", "bar", "baz", "qux"]; >> >> //Is there a simpler way to do the following than what�s here? >> var the_lookup = {}; >> the_array.forEach( function(i) { the_lookup.i = true } ); >> >> ======== >> >> In Perl this is easy: >> my @array = qw(foo bar baz qux); >> my %lookup = map { $_ => 1 } @array; >> >> >> Anything of the sort coming in JS, does anyone know? Maybe in some of >> the newer ES5 goodies? >> >> -FG >> > -- > Job Board: http://jobs.nodejs.org/ > Posting guidelines: > https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines > You received this message because you are subscribed to the Google > Groups "nodejs" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/nodejs?hl=en?hl=en > -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
