Is there a way to add try-catch to every function in Javascript?

user_316727 0
Viewed 26174

For error reporting, I would like to insert a try-catch wrapper around the code of every function I have.

So basically I want to replace 

function foo(arg){
   bar();
}

...with...

function foo(arg){
    try {
        bar() 
    }
    catch(e){
        customErrorHandler(e)
    }
}

Is there a way to apply this generic try-catch thing to all functions without manually editing all of them? For example by modifying the prototype of the Function object?

EDIT

Why I want to try-catch all my functions: I am building an HTML5 app that I'm publishing on iOS and Android. I can tell from my current rudimentary javascript error reporting that even though the app runs nicely on my own device, errors do occur on some other devices.

My objective is twofold: whenever a javascript error occurs on someone's device...

  1. I want to notify the user that the app may not function perfectly
  2. I want to know roughly where the error occurred, so I know where to look for the problem
error-handling prototype try-catch javascript
6 Answers

I don't have enough reputation to comment on the accepted answer.

I added a return before the f.apply to pass up the return value as well.

var tcWrapper = function(f) {
    return function() {
        try {
            return f.apply(this, arguments);
        } catch(e) {
            customErrorHandler(e)
        }
    }
}
user_84793440

The given answers already work well, just wanted to share a new one using closures.

Define wrapper

const tryCatchWrapper = (executable) => async (...args) => {
    try {
        const result = await executable(...args);
        return result;
    } catch (error) {
        // use any custom handler here
       error.message = `[${executable.name}] - ${error.message}`;
       error.data = {...error.data, input_args: args}
       throw error;
    }
}

Your function without a try-catch wrapper

const myFunction = async (x, y) => {
    const sum = x + y;
    if (sum > 10) throw new Error(`sum > 10 custom error`)
    return sum;
}

How to use it

try {
    const wrapperFunction = trycatchWrapper3(myFunction2);
    const output = await wrapperFunction(2, 93)
    console.log(output)
} catch (error) {
    console.error(error)
}

END

user_26964860
Related