What happens if I call a JS method with more parameters than it is defined to accept?

by

JavaScript doesn’t have the concept of a fixed parameter list. For your own functions you can always specify as many parameters as you want and pass in as many as you want which ever type you want.

For built-in functions, which correlate to native code, it depends.

You asked on what it depends:

Let’s look at the ECMA-262

Section 15 about built-in (not to confuse with host) functions in general

Unless otherwise specified in the description of a particular function, if a function or constructor described in this clause is given fewer arguments than the function is specified to require, the function or constructor shall behave exactly as if it had been given sufficient additional arguments, each such argument being the undefined value.

Alright. If I pass in less arguments than needed, it depends on the spec of the function itself (scroll down section 15 to find the spec for each built-in function).

Unless otherwise specified in the description of a particular function, if a function or constructor described in this clause is given more arguments than the function is specified to allow, the extra arguments are evaluated by the call and then ignored by the function. However, an implementation may define implementation specific behaviour relating to such arguments as long as the behaviour is not the throwing of a TypeError exception that is predicated simply on the presence of an extra argument.

Passing in too many arguments should never raise a TypeError. But still it may raise other errors. Again, it depends on the function you talk about.

You were talking explicitly about the DOM and not about built-in functions. To be honest I can’t find the corresponding parts of the spec. The ECMA spec is so much easier to read then the w3 website.

More Related Contents:

  1. How to receive and maintain values in functions (javascript)
  2. Set a default parameter value for a JavaScript function
  3. JavaScript variable number of arguments to function
  4. Is there a better way to do optional function parameters in JavaScript? [duplicate]
  5. ES6 destructuring function parameter – naming root object
  6. jQuery pass more parameters into callback
  7. Is it possible to get all arguments of a function as single object inside that function?
  8. Multiple arguments vs. options object
  9. What happens if I call a function with more arguments than it is defined to accept?
  10. Passing a function with arguments as an argument?
  11. Pass only the second argument in javascript
  12. I have returned two values but console displaying only one value.. what’s wrong with my code?
  13. I would like to ask how to explain this (javascript function)
  14. Pass an extra argument to a callback function
  15. Simplest/cleanest way to implement a singleton in JavaScript
  16. JavaScript function aliasing doesn’t seem to work
  17. How to turn a String into a JavaScript function call? [duplicate]
  18. Function declarations inside if/else statements?
  19. Calling a JavaScript function returned from an Ajax response
  20. What is “function*” in JavaScript?
  21. JavaScript function order: why does it matter?
  22. Higher-order functions in Javascript
  23. JavaScript curry: what are the practical applications?
  24. JavaScript: clone a function
  25. jQuery call function from a string [duplicate]
  26. $http.get(…).success is not a function
  27. Javascript – Precedence in hoisting
  28. Javascript: Get access to local variable or variable in closure by its name [duplicate]
  29. What are the different ways of writing an IIFE? What are their use cases?
  30. How to get function body text in JavaScript? [duplicate]

Leave a Comment