Variables and Constants

Basic Declaration

Each variable requires an explicit type followed by the name and, optionally, an initial value.

entero contador = 0
texto saludo = "Hola"
log activo = verdadero

If no value is provided, Quetzal assigns a default according to the type (0 for entero, 0.0 for numero, empty string for texto, falso for log).

Mutability

Variables are immutable by default. Use the var keyword to allow reassignments or methods that mutate the value.

entero var total = 10
total += 5

lista<texto> var elementos = ["a", "b"]
elementos.agregar("c")

Note

By default, all variables act as constants. Only variables declared with var can be modified after their initial assignment.

Valid Names

• Start with a letter or underscore and can contain numbers.
• Support camelCase or snake_case.
• Cannot match reserved words like si, lista, importar, nuevo, ambiente, verdadero, falso, nulo, y, o, no, and others listed in the reference section.

Scope

• Variables declared in the main body have global scope within the file.
• Inside functions or objects, scope is limited to the corresponding block.
• Each loop creates its own scope, so variables defined in the header or within the block are not visible outside of it.

entero var acumulado = 0
para (entero var numero en [1, 2, 3]) {
    acumulado += numero
}
// numero is no longer available here

Using ambiente

In objects, the reserved word ambiente allows access to internal attributes and methods.

objeto Contador {
    entero var valor = 0

    Contador(entero inicial) {
        ambiente.valor = inicial
    }

    vacio incrementar() {
        ambiente.valor++
    }
}

Symbolic Constants

Currently there is no specific keyword for global constants. To simulate a constant, declare the variable without var and avoid reassigning it. If you need to share it across multiple files, export it from a dedicated module.

texto MENSAJE_BIENVENIDA = "Bienvenido"
exportar { MENSAJE_BIENVENIDA }

Best Practices

• Prefer descriptive and consistent names.
• Declare variables as close as possible to their use.
• Avoid using mutability unless strictly necessary (e.g., accumulators or changing structures).