From: Zaidy036@air.isp.spam   
      
   On 9/3/2021 8:46 AM, Robert Prins wrote:   
   > On 2021-09-01 19:30, Tom Del Rosso wrote:   
   >> Here's a subroutine to get the length of a string that uses successive   
   >> approximation so it runs very fast because it only loops 13 times (once   
   >> for each bit of the resulting number) no matter how long the string is.   
   >>   
   >>   
   >> :GetStringLength   
   >> rem  Takes string variable NAME which must have no spaces. Returns   
   >> variable: StringLength   
   >> rem  Environment variables go up to 8191 characters so approximation   
   >> starts with 4096 which is the MSB.   
   >> rem  Practical limit is 8185 because "set x=" has 6 characters   
   >> if [%1]==[] set "StringLength=" & goto :eof   
   >> if not defined %1 set /a StringLength=0 & goto :eof   
   >> set /a GetStringLength_PlaceValue=4096   
   >> set /a GetStringLength_Guess=0   
   >> :GetStringLength_Loop   
   >> set /a GetStringLength_Guess^|=GetStringLength_PlaceValue   
   >> set /a GetStringLength_Skip=GetStringLength_Guess-1   
   >> call set "GetStringLength_Char=%%%1:~%GetStringLength_Skip%,1%%"   
   >> if not defined GetStringLength_Char set /a   
   >> GetStringLength_Guess^^=GetStringLength_PlaceValue   
   >> set /a GetStringLength_PlaceValue/=2   
   >> if %GetStringLength_PlaceValue% GTR 0 goto :GetStringLength_Loop   
   >> set /a StringLength=GetStringLength_Guess   
   >> set "GetStringLength_String="   
   >> set "GetStringLength_PlaceValue="   
   >> set "GetStringLength_Guess="   
   >> set "GetStringLength_Skip="   
   >> set "GetStringLength_Char="   
   >> goto :eof   
   >   
   >   
   > We're living in 2021, why write convoluted code when there are much   
   > better languages to do this? REXX (available for about every OS) can do   
   > it in one line, and if you only use Windoze, PowerShell would probably   
   > do it.   
   >   
   > Robert   
      
   another batch:   
      
   :: _StrngLen.bat   
      
   ::  _StrngLen.bat "string"             Length at exit   
   ::  _StrngLen.bat "string" _Len   Variable for length   
   :: https://ss64.com/nt/syntax-strlen.html   
      
   @ECHO OFF   
   ECHO(   
   FOR %%F IN (%1 %2 %3 %4 %5 %6 %7 %8 %9) DO CALL :LnCalc %%F   
      
   :EOF   
      
   :LnCalc   
   Setlocal EnableDelayedExpansion   
   :: strLen String [RtnVar]   
   ::             -- String  The string to be measured, surround in quotes   
   if it contains spaces.   
   ::             -- RtnVar  An optional variable to be used to return the   
   string length.   
   ECHO(   
   SET "s=#%~1"   
   SET "len=0"   
   For %%N in (4096 2048 1024 512 256 128 64 32 16 8 4 2 1) do (   
      if "!s:~%%N,1!" neq "" (   
        SET /a "len+=%%N"   
        SET "s=!s:~%%N!"   
      )   
   )   
   :: Endlocal & IF "%~2" neq "" (SET %~2=%len%) else ECHO %len% of %1   
   Endlocal & ECHO %len% of %1   
   GOTO :EOF   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)