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Syntax & Types
var const Static typing Type inference := Strings Arrays Dictionaries Enums StringName NodePath
Functions & Flow
func Return types Default parameters if elif else match for loop while loop break continue assert
Classes & Scripts
extends class_name Inner classes @export @onready static func setget properties super call is operator as casting
Nodes & Scene Tree
get_node % unique node add_child remove_child queue_free get_tree SceneTree groups PackedScene instantiate change_scene_to_file owner property
Signals
signal declaration emit signal connect signal Callable One-shot connection Signal arguments Await signal Built-in signals Disconnect signal Custom event bus
Resources & Files
Resource preload load @export Resource FileAccess open FileAccess store_string FileAccess get_as_text DirAccess JSON stringify JSON parse_string
Game Loop & Input
_ready _process _physics_process Input.is_action_pressed Input.is_action_just_pressed Input.get_vector CharacterBody2D velocity move_and_slide Timer await get_tree timer
Advanced Godot Patterns
Autoload singleton Tool scripts @tool @rpc Multiplayer authority Tween AnimationPlayer NavigationAgent2D Physics ray query Object pooling State machine
GDScript Complete Course / Functions & Flow

assert

Learn assert in GDScript with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.

10 min read • Beginner

assert is an atomic GDScript topic inside Functions & Flow. The example below uses the actual construct named by the lesson rather than a generic placeholder.

Focus on what assert changes: the input, binding, control path, object state, collection, runtime effect, or language contract. Then alter one value and verify that the behavior changes for a reason specific to this feature.

Topic-specific example

gdscript-02-10-assert.gd
gdscript Try It Live 
var qty := 2
assert(qty > 0, "quantity must be positive")
Edge case / engineering note

Exercise both the success path and the failure path; verify what is caught, propagated, or cleaned up rather than only checking printed output.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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