Tag Archives: haskell

Haskell Inspired zipWith() Function

Actionscript:
  1. initOperators();
  2.  
  3. trace(zipWith("-", [1,2,3], [1,2,3]));
  4. trace(zipWith("+", [1,2,3], [1,2,3]));
  5. trace(zipWith("*", [1,2,3], [1,2,3]));
  6. trace(zipWith("+", [1,1,1,3], [4,5,6,7]));
  7. trace(zipWith("<<", [2, 4], [1,1]));
  8. /*
  9. outputs:
  10.  
  11. 0,0,0
  12. 2,4,6
  13. 1,4,9
  14. 5,6,7,10
  15. 4,8
  16. */
  17.  
  18. function zipWith(op:String, a:Array, b:Array):Array{
  19.     var aLeng:int = a.length;
  20.     var bLeng:int = b.length;
  21.     var leng:Number = (aLeng <bLeng) ? aLeng : bLeng;
  22.     var zipped:Array = [];
  23.    
  24.     if (!this[op])return [];
  25.    
  26.     for (var i:int = 0; i<leng; i++){
  27.         zipped[i]=this[op](a[i], b[i]);
  28.     }
  29.     return zipped;
  30. }
  31.  
  32. function initOperators():void{
  33.     this["+"]=function(a:Number, b:Number):Number{ return a + b };
  34.     this["-"]=function(a:Number, b:Number):Number{ return a - b };
  35.     this["/"]=function(a:Number, b:Number):Number{ return a / b };
  36.     this["*"]=function(a:Number, b:Number):Number{ return a * b };
  37.     this["%"]=function(a:Number, b:Number):Number{ return a % b };
  38.    
  39.     this["&"]=function(a:Number, b:Number):Number{ return a & b };
  40.     this["<<"]=function(a:Number, b:Number):Number{ return a <<b };
  41.     this["|"]=function(a:Number, b:Number):Number{ return a | b };
  42.     this[">>"]=function(a:Number, b:Number):Number{ return a>> b };
  43.     this[">>>"]=function(a:Number, b:Number):Number{ return a>>> b };
  44.     this["^"]=function(a:Number, b:Number):Number{ return a ^ b };
  45. }

This snippet is basically like the haskell zipWith() function. It can combines two arrays into one array given a single function. In this case I defined a bunch of operator functions, but it would work with any kind of function that takes two arguments and returns a value. You could extend this to work with strings and do other strange things I guess.

If you have yet to go play with haskell ... go do it now.

Posted in Number, Operators, arrays, binary, functions, misc, return values | Also tagged , , | 2 Comments