Invalid get Index y with Vector2

Question

In Godot, I am making a 2D platformer, but in my player code I get the error:

Invalid get index 'y' (on base: 'int')

But only when the character touches the ground. My player code is this:

extends KinematicBody2D

const JUMP_FORCE = 1550
const MOVE_SPEED = 500
const GRAVITY = 60
const MAX_SPEED = 2000

var velocity = Vector2(0,0)
var can_jump = false

func _physics_process(delta):
    var walk = (Input.get_action_strength("right") - Input.get_action_strength("left")) * MOVE_SPEED
    
    velocity.y += GRAVITY
    
    velocity.x += walk
    move_and_slide(velocity, Vector2.UP)
    velocity.x -= walk
    
    velocity.y = clamp(velocity.y, -MAX_SPEED, MAX_SPEED)
    velocity.x = clamp(velocity.x, -MAX_SPEED, MAX_SPEED)
    
    var grounded = is_on_floor()
    if grounded:
        can_jump = true
        if velocity.y >= 5:
            velocity = 5
    elif is_on_ceiling() and velocity.y <= -5:
        velocity.y = -5
    
    if Input.is_action_just_pressed("jump"):
        if grounded:
            velocity.y = -JUMP_FORCE
        elif can_jump:
            can_jump = false
            velocity.y = -JUMP_FORCE

How do I fix this?

Answer 1

This is a close match to Invalid set index z with value of type float in gdscript. I would vote to close as duplicate but that question does not have an up-voted answer. Anyway, I will adapt the answer.

---

Types.

Look, velocity is a Variant, initialized to a Vector2:

var velocity = Vector2(0,0)

And - for example - here you use it as a Vector2:

    velocity.y = clamp(velocity.y, -MAX_SPEED, MAX_SPEED)
    velocity.x = clamp(velocity.x, -MAX_SPEED, MAX_SPEED)

But here 5 is an int not a Vector2:

            velocity = 5

So after that velocity... Continues to be a Variant, but now it has an int value. So when you use it as a Vector2 it fails. Because an int does not have x, y.

---

You can declare velocity to be a Vector2 explicitly:

var velocity:Vector2 = Vector2()

Or implicitly (inferred from the value you assigned):

var velocity:= Vector2()

And then Godot will tell you that this line:

            velocity = 5

Is an error, because you are trying to set an int to a Vector2.

---

You could either want to set only one component to 5, for example:

            velocity.y = 5

Or you want to set the length of the vector to 5, which you could do like this:

            velocity = velocity.normalized() * 5

Or you want to set both components to 5, which can be this:

            velocity.x = 5
            velocity.y = 5

Or this:

            velocity = Vector2(5, 5)

Write the code that you mean.