Improve reader performance on Firefox/Windows

Question

cljs.reader/read-string speeds up by a factor of 2 on Firefox/Windows through this change without complicating the code.

(Other JS engines, including Firefox on Linux/Mac do not seem to be affected as significantly.)

Answer 1

Comment made by: dnolen

It would be nice to have a bit more information on this ticket as to what Google Closure does that's unnecessary or whether this path is actually a faithful port of Clojure behavior (copies the implementation of the EDN reader in these hot spots??). Finally the patch names David Frese, have they submitted a CA?

Thanks!

Answer 2

Comment made by: sperber

I believe the Google functions are too general, work on strings in addition to characters etc.

It's not clear to us though why only Firefox on Windows benefits.

(David Frese is a co-worker - yes, has submitted a CA.)

Answer 3

Comment made by: mfikes

Patch no longer applies; needs re-baseline.
Also, doesn't work with {{git am}}; recommend creating patch using https://clojurescript.org/community/patches

Answer 4

Reference: https://clojure.atlassian.net/browse/CLJS-1827 (reported by alex+import)