container.sa

 
---------------------------> Sather 1.1 source file <--------------------------
-- container_alg.sa: Operations that work by inclusion on any container
-- Author: Benedict A. Gomes <gomes@tiramisu.ICSI.Berkeley.EDU>
-- Copyright (C) 1995, International Computer Science Institute
-- $Id: container.sa,v 1.3 1996/07/16 04:38:12 holger Exp $
--
-- COPYRIGHT NOTICE: This code is provided WITHOUT ANY WARRANTY
-- and is subject to the terms of the SATHER LIBRARY GENERAL PUBLIC
-- LICENSE contained in the file: Sather/Doc/License of the
-- Sather distribution. The license is also available from ICSI,
-- 1947 Center St., Suite 600, Berkeley CA 94704, USA.



abstract class $CONTAINER{ETP} < $ELT{ETP} 
abstract class $CONTAINER{ETP} < $ELT{ETP} is
   -- The basic abstract container type
   -- Does not have a create:SAME method, since this does not make sense
   -- for arrays and other indexible types, where the create should 
   -- take SAME as an argument
   -- Inherits: elt!, str

    copy: SAME;
    -- Return a copy of the current container
    -- post result = self

   size: INT;
   -- Number of elements actually inserted
   
   has(e: ETP): BOOL;
   -- pre ~void(self)
   -- True if the container contains the element "e"
   
   
end;


class CONTAINER_ALG{ETP,CTP<$CONTAINER{ETP}} 
class CONTAINER_ALG{ETP,CTP<$CONTAINER{ETP}} is
   
      filter!(c:CTP, once f:ROUT{ETP}:BOOL): ETP  pre ~void(c) is
      -- Yield all elements that satisfy the boolean predicate "f"
      loop
	 e ::= c.elt!;
	 if f.call(e) then yield e end
      end
   end;

   filter_not!(c:CTP, once f:ROUT{ETP}:BOOL): ETP  pre ~void(c) is
      -- Yield all elements that do not satisfy the boolean predicate "f"
      loop e ::= c.elt!; if ~f.call(e) then yield e end  end
   end;

   elt_if(c:CTP,test:ROUT{ETP}:BOOL,out res:ETP):BOOL is
      -- Return true if the container has an element that satisfies the
      -- predicate 'test'. The out argument 'res' is set to the 
      -- return value
      loop r ::= c.elt!; if test.call(r) then res:=r; return true; end;  end; 
      return false;
   end;
   
   count_if(c:CTP, test:ROUT{ETP}:BOOL):INT is
      -- The number of elements which satisfy `test'.
      r::=0; 
      loop if test.call(c.elt!) then r:=r+1 end   end;
      return r 
   end;

   some(c:CTP, test:ROUT{ETP}:BOOL):BOOL is
      -- True if some element of self satisfies `test'. 
      -- Self may be void.
      loop if test.call(c.elt!) then return true end  end;
      return false 
   end;

   every(c:CTP,test:ROUT{ETP}:BOOL):BOOL is
      -- True if every element of self satisfies `test'.
      -- Self may be void.
      loop if ~test.call(c.elt!) then return false end  end; 
      return true 
   end;

   notany(c:CTP,test:ROUT{ETP}:BOOL):BOOL is
      -- True if none of the elements of self satisfies `test'.
      -- Self may be void.
      loop if test.call(c.elt!) then return false end end; 
      return true 
   end;
   
   notevery(c:CTP, test:ROUT{ETP}:BOOL):BOOL is
      -- True if not every element of self satisfies `test'.
      -- Self may be void.
      loop if ~test.call(c.elt!) then return true end  end;
      return false 
   end;

end;