Script

• If a cell range is specified as an argument, it is expanded to the individual cell references contained in the range, and thus consumes an equal number of arguments as contained in the cell range.
• When an argument to a Script function is a reference to another cell that is returning a Blob, Edges, Histogram, or Patterns data structure, the object that is passed into the Script function is only usable until the Run Method returns. The Script function can directly return this object, and it is usable as the result value of the cell containing the Script function. However, if the script stores this object internally (using it in its Draw Method, for example), after the run method returns, the object is unusable, and attempting to call any of its methods results in an error. This also applies if the script returns a result structure such as a property of a script object returned by the run method. For instance, any of these properties are not be usable by a Get function, or by other Script functions, because the underlying objects are no longer valid.

• When writing a script, including code that validates input arguments can help to reduce errors, as shown in the example below:
  

                          function Tool()
  {
  }

  module.exports = Tool;
  
  function isNumber(n) {
     if (n === undefined || n == null || isNaN(parseFloat(n)) || !isFinite(n))
        return false;
     return true;
  }
  

  Tool.prototype.run = function(x, y){
     if (!isNumber(x) || !isNumber(y))
        throw new Error("Usage: Requires 2 numeric arguments");
     return +x + +y;
  } 

Script.prototype.run = function (image, myRegion) {

return {
    x: myRegion.x,
    y: myRegion.y,
    //width: myRegion.width,
    //height: myRegion.height,
    width: myRegion.w,
    height: myRegion.h,
    angle: myRegion.angle,
    curve: myRegion.curve
};

}