bug#25122: 24.5; function describe-variable hangs on large variables

[Thierry Volpiatto]

npostavs@users.sourceforge.net writes:

> I've been attempting an alternate approach which prettyprints the object
> while scanning it instead of the current way of printing and then
> reindenting.  Without optimizing, it's about 3 times as fast as the
> current pp (it's the pp-prin1 in the benchmarks below), though more than
> 3 times slower than your mapc pp trick.  On the other hand, it also
> doesn't yet handle function-specific indentation or any compound
> structure apart from lists, so I'm not sure if it will end up being much
> faster.
>
> (benchmark 1 '(with-temp-buffer (pp-prin1 long-list (current-buffer)) nil)) 
> "Elapsed time: 3.391232s (0.565806s in 11 GCs)"
> (benchmark 1 '(progn (pp-to-string long-list) nil))                         
> "Elapsed time: 9.988515s (0.148034s in 3 GCs)"
> (benchmark 1 '(progn (with-output-to-string (mapc 'pp long-list)) nil))     
> "Elapsed time: 0.983493s (0.144424s in 3 GCs)"
> (benchmark 1 '(progn (cl-prin1-to-string long-list) nil))                   
> "Elapsed time: 0.511617s (0.152483s in 3 GCs)"
> (benchmark 1 '(progn (prin1-to-string long-list) nil))                      
> "Elapsed time: 0.029320s"

Interesting, thanks to work on this.

-- 
Thierry