OpenEuphoria

Re: String compare

• Posted by Hawke <mdeland at NWINFO.NET> Sep 10, 1998
• 500 views

Roy Shepherd wrote:
> I'm trying to compare two strings.
> -- example
> object st
> st="ABC"
> if st="ABC" then puts(1,"OK") end if

another option, perhaps until you become more fluent in Euph's
syntax, besides the one offered by David
   (using compare(st,"abc") = 0 or the function solution below:
   --   function IsSame(object a,object b)
                return compare(a,b)=0
        end function
    )
another option might be to remember that (in essence) strings
are arrays (sequences) of characters.
you can walk the array, and you can use the = sign for
character comparisons.
   --constant Mary="Mary had a little piggy, whose fleece was skin"
   --to find out if a string has a 'p' in it, you can do
   --  for index = 1 to length(Mary) do
          if Mary[index] = 'p' then Found=TRUE end if
       end for
now, this is def'nly not the best way to test for string
equality, but for some cases, it works well, and it may
help you to think with sequences.

a hard coded 'compare' function would then look (actually, not
at all) like the following (in theory, as an algorithmic ex.):
   constant Mary1="mary had a little pig"
   constant Mary2="mary had a little gip"
   IsSame = FALSE
   --you need the following test, or the variable index will go out of
bounds
   if length(Mary1) = length(Mary2) then
      IsSame = TRUE
   end if
   index = 1
   while IsSame and (index <= length(Mary1)) do
      if Mary1[index] != Mary2[index] then
         IsSame=FALSE
      end if
      index = index + 1
   end while
   if IsSame then puts(1,"They match\n")
   else puts(1,"They do not match\n")
   end if

hopefully, this will help you see the slight differences in character
versus string equality??? hope so :)

enjoy--Hawke'