Your First Quetzal Program

In this tutorial you will create and run your first complete program in Quetzal Language, exploring the basic features of the language.

Hello, World!

Let’s start with the classic “Hello, World” program:

Create the file

Create a new file named hola_mundo.qz in your preferred folder.

Write the code

// My first program in Quetzal Language
consola.mostrar("Hola, mundo desde Quetzal!")

Run the program

Open Command Prompt or PowerShell in the folder where you saved the file and run:
Ventana de terminal
```
quetzal hola_mundo.qz
```
Expected result
```
Hola, mundo desde Quetzal!
```

Congratulations! You just ran your first program in Quetzal.

Complete Program Step by Step

Now let’s create a more complete program that demonstrates various features of the language:

Complete Code

Create a file named mi_primer_programa.qz:

/*
 My first complete program in Quetzal Language
 Author: Your name
 Date: Today
*/

consola.mostrar_exito("=== MY FIRST QUETZAL PROGRAM ===")

// ===== VARIABLES AND TYPES =====
consola.mostrar_informacion("1. Working with variables...")

// Basic types
entero edad = 25
texto nombre = "Ana Garcia"
numero salario = 2500.50
log esta_empleado = verdadero

// Display variables
consola.mostrar("Name: " + nombre)
consola.mostrar("Age: " + edad.texto() + " years")
consola.mostrar("Salary: $" + salario.texto())
consola.mostrar("Employed: " + esta_empleado.texto())

// ===== LISTS =====
consola.mostrar_informacion("2. Working with lists...")

lista<texto> hobbies = ["programar", "leer", "viajar", "cocinar"]
lista<entero> numeros_favoritos = [7, 13, 21, 42]

consola.mostrar("Hobbies: " + hobbies.texto())
consola.mostrar("Favorite numbers: " + numeros_favoritos.texto())

// ===== FUNCTIONS =====
consola.mostrar_informacion("3. Using functions...")

// Function to calculate circle area
numero calcular_area_circulo(numero radio) {
    numero pi = 3.14159
    retornar pi * radio * radio
}

// Function to create personalized greeting
texto crear_saludo(texto nombre_persona, entero edad_persona) {
    si (edad_persona >= 18) {
        retornar "Hello " + nombre_persona + ", you are an adult"
    } sino {
        retornar "Hello " + nombre_persona + ", you are a minor"
    }
}

// Use the functions
numero area = calcular_area_circulo(5.0)
texto saludo = crear_saludo(nombre, edad)

consola.mostrar("Circle area (radius 5): " + area.texto())
consola.mostrar(saludo)

// ===== CONDITIONALS =====
consola.mostrar_informacion("4. Using conditionals...")

entero puntuacion = 85

si (puntuacion >= 90) {
    consola.mostrar("Grade: Excellent")
} sino si (puntuacion >= 80) {
    consola.mostrar("Grade: Very Good")
} sino si (puntuacion >= 70) {
    consola.mostrar("Grade: Good")
} sino {
    consola.mostrar("Grade: Needs Improvement")
}

// ===== LOOPS =====
consola.mostrar_informacion("5. Using loops...")

consola.mostrar("Counting from 1 to 5:")
para (entero i = 1; i <= 5; i++) {
    consola.mostrar("Number: " + i.texto())
}

consola.mostrar("Iterating through hobbies:")
para (texto hobby en hobbies) {
    consola.mostrar("- " + hobby)
}

// ===== JSON OBJECTS =====
consola.mostrar_informacion("6. Working with JSON...")

jsn persona = {
    nombre: nombre,
    edad: edad,
    salario: salario,
    hobbies: hobbies,
    contacto: {
        email: "ana@example.com",
        telefono: "+502 1234-5678"
    },
    activo: verdadero
}

consola.mostrar("Person data:")
consola.mostrar(persona.texto_formateado())

// ===== MATHEMATICAL OPERATIONS =====
consola.mostrar_informacion("7. Mathematical operations...")

entero a = 15
entero b = 4

consola.mostrar("Operations with " + a.texto() + " and " + b.texto() + ":")
consola.mostrar("Sum: " + (a + b).texto())
consola.mostrar("Subtraction: " + (a - b).texto())
consola.mostrar("Multiplication: " + (a * b).texto())
consola.mostrar("Division: " + (a / b).texto())
consola.mostrar("Modulo: " + (a % b).texto())

// ===== MUTABLE VARIABLES =====
consola.mostrar_informacion("8. Mutable variables...")

entero var contador = 0
consola.mostrar("Initial counter: " + contador.texto())

contador = contador + 10
consola.mostrar("Counter after adding 10: " + contador.texto())

contador += 5
consola.mostrar("Counter after += 5: " + contador.texto())

// ===== END =====
consola.mostrar_exito("Program completed successfully!")
consola.mostrar("You have learned the basic concepts of Quetzal Language")

Run the Program

quetzal mi_primer_programa.qz

Understanding the Code

In Quetzal, variables are declared with their type first:

entero edad = 25           // Integer
texto nombre = "Ana"       // String
numero precio = 99.99      // Decimal number
log activo = verdadero     // Boolean

By default, variables are immutable. Use var for mutable variables:

entero var contador = 0
contador = contador + 1    // This works

Functions are defined with their return type, name, and parameters:

numero calcular_area(numero radio) {
    retornar 3.14159 * radio * radio
}

// Function without return value
vacio mostrar_mensaje(texto mensaje) {
    consola.mostrar(mensaje)
}

Conditionals use si, sino si, and sino:

si (edad >= 18) {
    consola.mostrar("Adult")
} sino si (edad >= 13) {
    consola.mostrar("Teenager")
} sino {
    consola.mostrar("Child")
}

Quetzal supports multiple loop types:

// Traditional for loop
para (entero i = 0; i < 5; i++) {
    consola.mostrar(i.texto())
}

// For-each loop
para (texto item en lista) {
    consola.mostrar(item)
}

// While loop
mientras (condicion) {
    // code
}

Next Steps

Basic Syntax

Dive deeper into the language syntax and structure.

Learn syntax

Data Types

Explore all available data types and their methods.

View types

Functions

Learn about functions, parameters, and return values.

Learn functions

More Examples

Explore more practical examples and projects.

View examples