Structures

Basic Usage

Product types are defined using the struct keyword.

def Person := struct
  name: str
  age: int

This produces a Person type with name and age fields.

You can make a Person value like this:

def person := Person.mk "Alice" 30

You can access the fields of a Person value like this:

def name := person.name
def age := person.age

Struct Methods

All methods with the first EXPLICIT argument are considered struct methods.

def greet(person: Person) := "Hello, " + person.name
def greet_msg : str := (Person.mk "Alice" 30).greet

Thanks to currying, you can write something like this:

def greet (person: Person) (age : int) := "Hello, " + person.name
def greet_alice : int -> str := (Person.mk "Alice" 30).greet
def greet_alice_age : str := greet_alice 30