The Numeric for Loop

Part of the Fundamentals section of Coddy's Lua journey — lesson 73 of 90.

When you need to repeat code a specific number of times, the numeric for loop is your best choice. Unlike while and repeat-until loops that depend on changing conditions, the numeric for loop automatically handles the counting for you.

The basic syntax looks like this:

for variable = start, finish do
    -- code to repeat
end

Here's a simple example that prints the numbers 1, 2, and 3:

for i = 1, 3 do
    print(i)
end

The loop creates a variable i that starts at 1 and automatically increases by 1 each time through the loop. When i reaches 3, the loop runs one final time and then stops.

You don't need to manually update the counter variable - Lua handles this automatically.

This makes numeric for loops perfect for situations where you know exactly how many times you want something to happen, like printing a message multiple times, processing each item in a list, or counting through a range of numbers.

Challenge

Easy

Create a training session tracker that uses a numeric for loop to simulate multiple workout repetitions. Write a for loop that runs from 1 to 5, representing 5 training rounds.

Inside the loop, print the message "Training round: " followed by the current round number. This will help you practice the basic numeric for loop syntax and understand how the loop variable automatically increments.

Cheat sheet

The numeric for loop repeats code a specific number of times with automatic counting:

for variable = start, finish do
    -- code to repeat
end

Example that prints numbers 1, 2, and 3:

for i = 1, 3 do
    print(i)
end

The loop variable automatically starts at the start value and increases by 1 each iteration until it reaches the finish value.

Try it yourself

-- TODO: Write your code here
-- Use a for loop to iterate from 1 to 5
-- Print "Training round: " followed by the round number for each iteration

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Fundamentals

1Introduction

The Language Hello World!Comments

4Operators 2 Relational & Logic

Equality Operators Relational Operators The 'and' Operator The 'or' Operator The 'not' Operator Short-Circuit Evaluation Truthy and Falsy Values Recap - Simple Logic

7Basic Conditional Logic

The if-then Statement The if-then-else Statement The elseif Statement Recap - Treasure Chest

10Tables Part 1: List-Style

What is a Table?Creating a Table Accessing Elements by Index Modifying Elements by Index The Length Operator '#'table.insert()table.remove()Recap - Manage Party Members

13Project: Simple Potion Shop

Project Setup Adding a Potion

Displaying the Inventory

Calculating Total Stock Value

Finding a Specific Potion

Selling a Potion

3Operators 1 Arithmetic & Conc

Arithmetic Operators Modulo Operator Exponentiation Operator String Concatenation Operator Precedence Recap - Simple Calculations

6Project: Character Stats Disp

Welcome Message Declare Character Stats

Display Basic Stats

Add a Boolean Flag

Final Summary

9Functions Basics

Declaring a Function Calling a Function Functions with Parameters Functions with Multiple Params The 'return' Statement Recap - Area Calculator

12Loops Basics

The while Loop The repeat-until LoopThe Numeric for Loopfor Loop with a Step The 'break' Statement Recap - Countdown

15Final Challenges

Recap - Player Turn Recap - Simple Database Recap - Sum of Even Numbers