OpenEuphoria

Re: type string

• Posted by "Boehme, Gabriel" <gboehme at MUSICLAND.COM> Mar 15, 1999
• 616 views

Daniel Berstein <daber at PAIR.COM> wrote:

>>Running on a PII 200mHz in DOS under WinNT:
>> -------------------------------------------
>>exw strbench 100000 6
>>
>>string6z() - 0.001285 "c<0" replaced with "c<1"
>>string6()  - 0.001288
>>string6s() - 0.001304 "not sequence(s)" replaced with "atom(s)"
>>string6i() - 0.001324 "integer(c)" replaced with "atom(c)"
>>string()   - 0.001344
>>

[snip]

>BTW I avoided some of the randomness of the benchmark under NT using
>exw.exe instead of ex.exe (and the numbers returned are much more "real"
>than those 0.00xxx seconds ex.exe gives).


You're right:

Running EXW in WinNT:
 ---------------------
exw strbench 400000 6

string8  -- 5.890000 almost identical to string6 [see below]
string6i -- 6.020000 "integer(c)" replaced with "atom(c)"
string   -- 6.096667
string6z -- 6.165000 "c<0" replaced with "c<1"
string6  -- 6.173333
string8i -- 6.241667 almost identical to string6i [see below]
string6s -- 6.273333 "not sequence(s)" replaced with "atom(s)"


 -- the runner-up
global type string6i(object s)
   object c
   if not sequence(s) then
      return 0
   end if
   for i = 1 to length(s) do
      c = s[i]
      if atom(c) then
         if (c < 0) or (c > 255) then
            return 0
         end if
      else
         return 0
      end if
   end for
   return 1
end type

 -- almost the loser
global type string8i(sequence s) -- notice
   object c
   for i = 1 to length(s) do
      c = s[i]
      if atom(c) then
         if (c < 1) or (c > 255) then
            return 0
         end if
      else
         return 0
      end if
   end for
   return 1
end type

 -- the winner!
global type string8z(sequence s) -- ditto
   object c
   for i = 1 to length(s) do
      c = s[i]
      if integer(c) then
         if (c < 1) or (c > 255) then
            return 0
         end if
      else
         return 0
      end if
   end for
   return 1
end type


Apparently, Euphoria can optimize the "integer" test much better when the
incoming object is required to be a sequence. Otherwise, the "atom" test
wins out.


Be seeing you,
   Gabriel Boehme


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The obligatory quote:

Nothing worthwhile is achieved suddenly.

Robert Fripp
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