FunctionLogger: includescript to log function calls and its parameters for debugging

Buttons/Scripts
1

Debugging Dopus scripts can be hard and basically is logging values. This include script aims to help in this process by replacing the call to the function with a call to LogFunction but maintaining the parameters so the impact on your code is minimal.

Your old code

function MyFunction(a, b) 
{
    DOpus.Output("Myfunction(" + a + ", " + b + ")");
    return a + b; 
}
var result = MyFunction(1, 2);

becomes

function MyFunction(a, b) { return a + b; }
var result = LogFunction(MyFunction, 1, 2);

and outputs
"Calling MyFunction(a = 1, b = 2)"

inc_FunctionLogger.opusscriptinstall (v 1.1, 1.4 KB)

inc_FunctionLogger.opusscriptinstall (v1.0, 996 Bytes)

inc_FunctionLogger.js 
// FunctionLogger
// (c) 2026 Felix.Froemel

// This is an include file script for Directory Opus.
// See https://www.gpsoft.com.au/endpoints/redirect.php?page=scripts for development information.

// Called by Directory Opus to initialize the include file script
function OnInitIncludeFile(initData)
{
	initData.name = "FunctionLogger";
	initData.version = "1.1";
	initData.copyright = "(c) 2026 Felix.Froemel";
	initData.url = "https://resource.dopus.com/t/functionlogger-includescript-to-log-function-calls-and-its-parameters-for-debugging/58532";
	initData.desc = "";
	initData.min_version = "13.0";
	initData.shared = true;
}

//Log a function and its param values
function LogFunction(fn) 
{
	var params = [];
	var paramNamesAndValues = [];
  	for (var i = 1; i < arguments.length; i++)
	{
		params.push(arguments[i]);
		paramNamesAndValues.push(String(arguments[i]));
	}

	var funcName = GetFunctionName(fn);
	var funcParamNames = GetFunctionParameterNames(fn);
	var paramNamesAndValues = MergeParamNamesAndValues(funcParamNames, paramNamesAndValues);
	  
	DOpus.Output("Calling " + funcName + "(" + paramNamesAndValues + ")");
  
  	return fn.apply(null, params);
}

//Get the name of a function
function GetFunctionName(fn)
{
	var funcStr = fn.toString();
	var name = funcStr.substr("function ".length);
	name = name.substr(0, name.indexOf("("));
	return name;
}

//Get the names of the parameters of a function
function GetFunctionParameterNames(fn)
{
	var funcStr = fn.toString();
    var matches = funcStr.match(/function\s+\w+\s*\(([^)]*)\)/);
    
    if (!matches)
        return [];
    
    var paramsString = matches[1];
    
    if (paramsString === '')
        return [];
    
	var params = paramsString.split(',');
	for(var i = 0; i < params.length; i++)
		params[i] = params[i].replace(/^\s+|\s+$/g, ""); //trim
    return params;
}

//combine param names and values to paramName = paramValue
function MergeParamNamesAndValues(names, values)
{
	if(names.length != values.length)
	{
		DOpus.Output("Function Logger: param names do not match values", true);
		return "";
	}

	var result = "";
	for(var i = 0; i < names.length; i++)
	{
		var seperator = i < names.length - 1 ? ", " : "";
		result += names[i] + " = " + values[i] + seperator;
	}
	return result;
}
2

Version 1.1 now logs also the names of the parameters. Example output

Calling MyFunction(a = 1, b = 2)