string match vs regexp, which is faster?

[Dedan]

I have no way of testing the speed of these commands.
does anyone have the time and means to test this for me?

Code: Select all

set e "entry"

proc test_speed {text} {
  global e

  if {[string match -nocase "*$e*" "$text"]} {

  if {[regexp -nocase {$e} $text]} {

}

thanks for any help given

[demond]

I have no way of testing the speed of these commands.

yes you have

it's called time

[Dedan]

does this sound right to you?

[11:28] < Isa >. stringmatching is 25 microseconds per iteration : Notice
[11:28] < Isa >. regexping is 21721 microseconds per iteration : Notice

i thought regexp would be much faster

Code: Select all

set e "entry"


bind pubm -|- * test_speed

proc test_speed {nick uhost handle chan text} {
  global e
  set stringmatch [time {string match -nocase "*$e*" "$text"} 1]
  set regexping [time {regexp -nocase {$e} $text} 1]
  putquick "NOTICE $nick :stringmatching is $stringmatch"
  putquick "NOTICE $nick :regexping is $regexping"
}

[demond]

your repetition count of 1 screws the results, but yes, generally [string match] is always faster than [regexp] since the code it translates to is much more simple and optimized

more accurate results:

Code: Select all

[demond@whitepine demond]$ tclsh8.4
% set a blah
blah
% time {regexp -nocase $a skldjfsdfblah290387423890} 1000
7 microseconds per iteration
% time {string match -nocase *${a}* skldjfsdfblah290387423890} 1000
2 microseconds per iteration