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How to Check if an Array Is Null in Godot Without Errors

Ethan Martinez

Working with arrays in Godot can be super fun—until you bump into a sneaky little error because an array wasn’t properly checked. Suddenly, your game crashes, and you’re staring at a line of code that didn’t look broken a second ago. Worry not! We’ve got you covered with a playful but practical guide to checking if an array is null—without causing chaos in your game.

TL;DR

To check if an array is null in Godot without getting errors, use simple checks like if my_array == null or if typeof(my_array) == TYPE_NIL. Avoid blindly accessing elements or using methods before confirming the array exists. This protects your game from unwanted crashes and confusing bugs. Keep your code clear and safe with easy conditionals!

What is a Null Array Anyway?

Let’s start with the basics. A null array means the array doesn’t exist yet or hasn’t been set up in your code. It’s not empty—it’s just… nothing.

  • Null: The variable was never assigned a value.
  • Empty: The array exists but has zero elements.

That’s a big difference when you’re coding!

Why You Should Care

If you try to use a method on a null array, like my_array.size(), Godot throws an error. You didn’t even get to the fun part of your game! Game over for your playtest.

To prevent this, always make sure your array exists before using it.

How to Check for Null Properly

Now comes the good part—simple, safe checks to keep your project running smoothly.

1. Check with == null


if my_array == null:
    print("Yep, it's null.")

This is the easiest and clearest way. It asks, “Hey, do you even exist?” and proceeds accordingly.

2. Use typeof() for Extra Safety


if typeof(my_array) == TYPE_NIL:
    print("Array has never been set.")

This method lets you check the data type directly. Safer. Smart. Sharp!

3. Combine with Size Check

Want to know if the array is not null and has something in it? 


if my_array != null and my_array.size() > 0:
    print("Array is good and not empty.")

This is a powerful one-two punch!

But Wait! What About Empty Arrays?

Sometimes the array exists but doesn’t have anything in it. That’s different from being null. 


var my_array = []

This array is not null, but it is empty.

Check it like this:


if my_array.size() == 0:
    print("Not null, but nothing's inside!")

You’re not just coding—you’re detective-ing. 🎩🔍

Danger Zones: What NOT to Do

Let’s look at some common mistakes. These can make your game say, “Nope!” and refuse to run.

1. Access Before You Check


# BAD IDEA ↓↓↓
print(my_array.size())  # If my_array is null, this breaks

Why? Godot will scream at you because you’re asking a ghost if it has shoes. Don’t do it.

2. Blindly Looping


# Uh oh
for thing in my_array:
    print(thing)

If my_array is null, the loop throws an error. Check first!

Use:


if my_array != null:
    for thing in my_array:
        print(thing)

When Do Arrays Become Null?

Godot doesn’t always set arrays for you. If you declare an array but don’t assign it right away, it’s null. 


var my_array

At this point, my_array is null. Until you assign [] or something else, it stays that way forever.

So, What Should You Do?

Use Defaults

Assign something to your arrays when you create them!


var my_array = []

Now you don’t even have to worry about null anymore. It starts empty, not invisible.

Make Helper Functions

Create small helper functions to guard your array usage. Example: 


func is_valid_array(arr):
    return arr != null and typeof(arr) == TYPE_ARRAY

Now just do this:


if is_valid_array(my_array):
    print("Safe to use!")

Bonus! Detecting Array Type

Want to double-check the type for total confidence?


if typeof(my_array) == TYPE_ARRAY:
    print("It's a real array.")

This makes sure you’re not working with a string or number by accident.

Real-World Use Case

Let’s say you’re making a game with inventory. You expect the inventory to be an array:


var inventory

Maybe later, items are added:


inventory.append("Sword")

💥 Boom! Your code breaks. You tried to add an item to “nothing.”

Solution? Initialize it ahead of time:


var inventory = []

And always check before you use it:


if inventory != null:
    inventory.append("Sword")

No more surprises!

Wrap Up: Stay Safe, Array Master!

  • Use == null or typeof(var) == TYPE_NIL
  • Don’t call methods on possibly null arrays
  • Initialize arrays to [] when declaring
  • Check for size() only after confirming it’s not null

Now you’re ready to conquer the world of arrays in Godot without crashing your dreams—or your game!

Final Tip:

Remember: It’s better to write one extra line of code than to spend hours tracking a crashing bug. Happy coding!

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