Posted to tcl by kbk at Sun Nov 21 02:16:38 GMT 2010view pretty
$ ./tcltest
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000
4.573238 microseconds per iteration
% set tcl_precision 17
17
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000
4.2633270000000003 microseconds per iteration
% set tcl_precision 12
12
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000
4.001461 microseconds per iteration
% exit
$ tclsh8.5
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000; # horrible before the fix
28.523233 microseconds per iteration
% set tcl_precision 17
17
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000
5.4804399999999998 microseconds per iteration
% set tcl_precision 12
12
% set i 0
0
% time {set a [expr {[incr i]*1e-9}]x} 1000000
5.202241 microseconds per iteration
% exit