nil.md

Nil

Introduction

What is Nil ?

In Luau, nil serves as a representation of non-existence or nothingness. It stands apart from other values and data types, allowing you to effectively eliminate variables or remove values from tables. Notably, nil and false are the only values that do not evaluate to true.

Luau incorporates a garbage collector designed to remove data that scripts no longer access. To optimize performance, consider redefining large variables as nil in lengthy scripts when they are no longer necessary, facilitating their removal by the garbage collector.

Basic Usage

local variableToDelete = 5
print(variableToDelete) -- 5

-- Set variable to nil for removal
variableToDelete = nil
print(variableToDelete) -- nil

In Tables

local dictionaryTable = {
	Monday = 1,
	Tuesday = 2,
	Wednesday = 3
}

-- Access and output value of 'Tuesday' key
print(dictionaryTable.Tuesday) -- 2

-- Clear 'Tuesday' key using nil
dictionaryTable.Tuesday = nil

-- Output value of key again (now nil)
print(dictionaryTable.Tuesday) -- nil

Removing Objects from View

You can utilize nil to clear properties of objects, effectively removing them from the experience. For instance, setting the Parent of an object to nil removes it from view. To reintroduce the object, simply reassign the Parent. The following example illustrates using nil to manage the visibility of a Part:

-- Create a new brick
local part = Instance.new("Part")

-- Parent new Part to the workspace, making it viewable
part.Parent = workspace
task.wait(1)

-- Remove the Part from view (not from memory)
part.Parent = nil
task.wait(1)

-- Reintroduce the Part to view
part.Parent = workspace
task.wait(1)

-- Remove the part from view again
part.Parent = nil

-- Clear part reference for garbage collector
part = nil

Conclusion

By adopting these simple practices, you can harness the power of nil in Luau to manage variables, tables, and objects effectively.