Lady, EVOLVED 
browser engines
webkit is still the only one which lets you do proper functional programming, huh
re: browser engines
; { const sum = (() => {"use strict"; return (x,i=0) => x === 0 ? i+x : sum(x-1,i+x)})(); sum(5000000) }
Works On My Machine
re: browser engines
@aescling anyway it could mean something in practice if you built your JS runtime on top of JavaScriptCore instead of V8…
re: browser engines
@aescling technically it is not “tail call optimization” but “proper tail calls”, meaning that tail calls can’t overflow the stack, but they don’t have to be any faster than other calls (some complain PTC is actually harder to optimize)