This solution is attempting to use duck-typing, however it is a problematic approach because the length property could be added to an Object.

obj = {};
obj.length = 0;

obj.hasOwnProperty('length') // => true
obj.toString() // => "[object Object]"

This solution is attempting to use duck-typing, however it is a problematic approach because the length property could be added to an Object.

obj = {};
obj.length = 0;

obj.hasOwnProperty('length') // => true
typeof obj // => "[object Object]"

On top of that, you are using an if/else statement, when you could just return value.hasOwnProperty('length') (even though hasOwnProperty is not the best approach).

This solution is attempting to use duck-typing, however it is a problematic approach because the length property could be added to an Object.

obj = {};
obj.length = 0;

obj.hasOwnProperty('length') // => true
typeof obj // => "[object Object]"

Except that the description says to append "..." to the returned string, so you would have to check that limit+3 === returnValue.length.

I just tried to submit my solution and it failed me because it says solution("Test", 10) did not return "Test" even though my code was correct as described by the instructions.

Dropping curly braces in JavaScript is a bad practice. It can lead to unexpected behavior due to JavaScript auto-semicolon-insertion feature.

Consider the following:

function broken() 
{
  return
  {
    state: 'broken'
  }
}

// what would this output?
console.log(broken())

Dropping curly braces in JavaScript is a bad practice. It can lead to unexpected behavior due to JavaScript auto-semicolon-insertion feature.

Consider the following:

function broken() 
{
  return
  {
    state: 'broken'
  }
}

// what would this output?
console.log(broken())

Define the toString method by assigning it to the constructor's prototype.

It's better to throw an error here than assign empty strings if the right parameters are not given. How will you debug code like this?

Completely unmaintainable.

Why?

The other downside is that assigning the toString method here means that every time a new Animal is constructed, the toString method needs to be assigned. The drawbacks here are

• the interpreter is doing a lot of unnecessary work
• the method is not inherited by sibling objects (objects also created with the Animal constructor) which means that
• overriding the method is only possible on a per-instance basis (you cannot override the method and have it apply to every instance)

This solution should be considered "incorrect".