JavaScript closure vs. object look-up performance

from blog marijnhaverbeke.nl/blog, | ↗ original
Note: the question asked in this post, "why aren't closures super-fast?", was thorougly answered by Vyacheslav Egorov in his followup. Reading that is probably more informative than reading the text below. I originally structured CodeMirror instances as one huge closure that contained all the internal variables. The constructor would create local...