Hello World in SAPL

Learn how to write your first program in SAPL, the Simple Amharic Programming Language.

Learning Objectives

Understand the basic structure of a SAPL program
Create and run your first SAPL script
Learn how to use the SAPL REPL for interactive coding
Understand how to use the አሳይ() function for output

Introduction

Welcome to SAPL (Simple Amharic Programming Language)! In this tutorial, we'll write our first SAPL program: a simple "Hello, World!" application. This is traditionally the first program developers write when learning a new programming language, as it demonstrates the basic syntax and structure required to produce output.

Prerequisites

Before you begin, ensure you have the following:

SAPL installed on your system (version 1.0 or higher)
A text editor for writing code (VS Code, Sublime Text, Notepad++, etc.)
Basic familiarity with using the command line or terminal

Verify Installation

You can verify your SAPL installation by running sapl --version in your terminal.

Method 1: Using the SAPL REPL

The simplest way to try SAPL is through its REPL (Read-Eval-Print Loop), which allows you to write and execute code interactively. This is perfect for experimenting with small code snippets and learning the language.

Steps:

Open your terminal or command prompt
Run the SAPL interpreter
sapl
You should see a prompt that looks like this: >>>
Type the following code and press Enter:
```
አሳይ("ሰላም ዓለም!")
```
SAPL
View the output:
ሰላም ዓለም!

Congratulations!

You've just written and executed your first SAPL command. The አሳይ() function displays the text inside the parentheses on the screen.

Method 2: Creating a SAPL Script File

For more complex programs or code you want to save and reuse, it's better to write your code in a file. Let's create a SAPL script file for our Hello World program.

Steps:

Open your text editor and create a new file
Name the file hello.sapl (SAPL files use the .sapl extension)

Add the following code to the file:

# የመጀመሪያ ፕሮግራም

አሳይ("ሰላም ዓለም!")

SAPL

Save the file
Open your terminal or command prompt
Navigate to the directory where you saved the file
Use cd command to change directories, e.g., cd Documents/sapl-projects
Run the script using the SAPL interpreter:
sapl hello.sapl
View the output:
ሰላም ዓለም!

Understanding the Code

Let's break down what's happening in our simple program:

# የመጀመሪያ ፕሮግራም

This is a comment in SAPL. Comments start with # and are ignored by the interpreter. They're useful for adding notes to your code in either Amharic or English.

አሳይ("ሰላም ዓለም!")

This calls the አሳይ function with the string "ሰላም ዓለም!" as an argument. The function displays the text on the screen. Note that text strings must be enclosed in quotation marks.

Extending the Program

Let's make our program a bit more interesting by adding a variable and using string concatenation:

# የተሻሻለ ሰላም ዓለም ፕሮግራም

ስም = "ሳፕል"
አሳይ("ሰላም ዓለም! እኔ " + ስም + " ነኝ።")
አሳይ("ፕሮግራሚንግን በአማርኛ እንማር!")

SAPL

What's New:

ስም = "ሳፕል" - Creates a variable named ስም (name) and assigns it the value "ሳፕል"
አሳይ("ሰላም ዓለም! እኔ " + ስም + " ነኝ።") - Uses the + operator to concatenate (join) strings together with the variable
Multiple አሳይ() statements to display multiple lines of output

Important Note

In SAPL, variables are case-sensitive and can contain Amharic characters. Choose meaningful variable names to make your code more readable.

Common Errors and Troubleshooting

Missing Quotation Marks

አሳይ(ሰላም ዓለም!)

Error: Strings must be enclosed in quotation marks. The correct syntax is:

አሳይ("ሰላም ዓለም!")

Incorrect Function Name

asay("ሰላም ዓለም!")

Error: SAPL uses Amharic function names. The correct function name is አሳይ, not asay.

Missing Parentheses

አሳይ "ሰላም ዓለም!"

Error: Function arguments must be enclosed in parentheses. The correct syntax is:

አሳይ("ሰላም ዓለም!")

Summary

Key Concepts Learned

How to use the SAPL REPL for interactive coding
How to create and run a SAPL script file
How to use the አሳይ() function to display output
How to create variables and perform string concatenation
How to add comments to your code

Congratulations! You've successfully written your first SAPL program. This is just the beginning of your journey with SAPL. As you continue through these tutorials, you'll learn more advanced concepts and techniques for building powerful programs.

Next Steps

Now that you've completed this tutorial, you're ready to move on to more advanced topics:

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