Basic Syntax

Quetzal Language uses clean syntax without semicolons. Each instruction occupies its own line or block, and keywords are in Spanish.

Comments

// Single line comment

/*
 Multi-line comment
 that can include line
 breaks.
*/

entero valor = 42  // Comment next to code

Primitive Types

Type	Description	Example
vacio	Absence of value (functions only)	-
entero	Signed integers	entero edad = 27
numero	Floating point values	numero pi = 3.14159
texto	Unicode strings	texto saludo = "Hola"
log	Boolean values	log activo = verdadero

entero edad = 27
numero temperatura = 22.5
texto mensaje = "Hola"
log activo = verdadero

Tip

The types numero and número are equivalent (with or without accent).

Lists

Lists are declared with lista and can be typed or untyped.

// Typed list
lista<entero> numeros = [1, 2, 3]
lista<texto> nombres = ["Ana", "Luis"]

// Untyped list (can contain any type)
lista valores = [1, "dos", verdadero]

// Empty list
lista<texto> vacia = []

Mutable lists use var and allow methods like agregar, ordenar, or sumar.

lista<texto> var frutas = ["manzana", "naranja"]
frutas.agregar("pera")
consola.mostrar(frutas.texto())

JSON Values (jsn)

jsn var persona = {
    nombre: "Ana",
    edad: 30,
    activo: verdadero,
    direcciones: [
        { tipo: "casa", ciudad: "Guatemala" },
        { tipo: "trabajo", ciudad: "Antigua" }
    ]
}

texto ciudad = persona.direcciones[0].ciudad
persona.establecer("activo", falso)

Variables and Mutability

Variables are immutable by default. Use the var keyword to allow reassignments or mutating methods.

entero contador = 10          // Immutable (constant)
entero var mutable = 5        // Mutable (variable)
mutable += 1

lista<entero> var datos = [1, 2]
datos.agregar(3)

Operators

Arithmetic

entero a = 7
entero b = 3

entero suma = a + b        // 10
entero resta = a - b       // 4
entero producto = a * b    // 21
entero cociente = a / b    // 2
entero residuo = a % b     // 1

Increment and Decrement

entero var valor = 5

valor++   // valor = 6
valor--   // valor = 5

Comparison

log igual = a == b         // falso
log distinto = a != b      // verdadero
log mayor = a > b          // verdadero
log menor = a < b          // falso
log mayor_igual = a >= b   // verdadero
log menor_igual = a <= b   // falso

Logical

log condicion1 = verdadero
log condicion2 = falso

// Spanish operators
log conjuncion = condicion1 y condicion2    // falso (AND)
log disyuncion = condicion1 o condicion2    // verdadero (OR)
log negacion = no condicion1                // falso (NOT)

// Symbolic operators (equivalent)
log and_result = condicion1 && condicion2   // falso
log or_result = condicion1 || condicion2    // verdadero
log not_result = !condicion1                // falso

Compound Assignment

entero var total = 10

total += 5    // total = 15
total -= 3    // total = 12
total *= 2    // total = 24
total /= 4    // total = 6
total %= 4    // total = 2

Ternary Operator

entero edad = 20
texto mensaje = edad >= 18 ? "Mayor de edad" : "Menor de edad"

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Text Interpolation

Interpolated strings are declared with the t prefix and allow embedding expressions within braces {}.

Basic Syntax

texto nombre = "Maria"
entero edad = 25

// Basic interpolation
texto saludo = t"Hola, {nombre}!"
texto info = t"{nombre} tiene {edad} anos"

consola.mostrar(saludo)  // "Hola, Maria!"
consola.mostrar(info)    // "Maria tiene 25 anos"

With Expressions

You can include any valid expression inside the braces:

entero a = 10
entero b = 5

texto operaciones = t"Sum: {a + b}, Difference: {a - b}, Product: {a * b}"
// "Sum: 15, Difference: 5, Product: 50"

texto comparacion = t"Is {a} greater than {b}? {a > b}"
// "Is 10 greater than 5? verdadero"

With Different Types

Interpolation automatically converts values to text:

numero precio = 99.99
log disponible = verdadero
lista numeros = [1, 2, 3]

texto producto = t"Price: ${precio}, Available: {disponible}"
texto lista_info = t"Numbers: {numeros}"

jsn datos = { nombre: "Juan", edad: 30 }
texto json_info = t"Data: {datos}"

Multiline Interpolation

texto nombre = "Juan"
entero puntos = 150

texto mensaje = t"Dear {nombre},
Your {puntos} points are available.
Thank you for using Quetzal!"

consola.mostrar(mensaje)

Escaping Braces

To show literal braces, use double backslash:

entero valor = 42
texto con_llaves = t"The value is {valor} and these are braces: \\{literal\\}"
// "The value is 42 and these are braces: {literal}"

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Basic Input and Output

The consola methods allow sending messages and requesting data.

Display Messages

consola.mostrar("Normal message")
consola.mostrar_exito("Successful operation")
consola.mostrar_error("An error occurred")
consola.mostrar_advertencia("Important warning")
consola.mostrar_informacion("Useful information")

Request Input

texto nombre = consola.pedir("Enter your name: ")
consola.mostrar_exito(t"Welcome, {nombre}")

// Hidden input (for passwords)
texto clave = consola.pedir_secreto("Enter your password: ")

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Null Value

The nulo literal represents the absence of value and can be assigned to any type:

entero valor_nulo = nulo
texto mensaje_nulo = nulo
lista<entero> lista_nula = nulo
jsn json_nulo = nulo

Caution

Attempting to use a nulo value in operations can cause errors. Always verify before operating.

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With these elements you can read the rest of the fundamentals and build more complex programs.