Skip to main content

Types

Paraflow has typed inputs to events, functions and skills, and performs type inference through goals and variables where possible. Optional return types can be specified on events, functions and skills.

e.g.:

skill test/basic($input string) object { title string } {
  return { title: $input + ": Part 2" };
}

Arrays​

Array types can be specified using array[T] where T is the inner type, e.g. array[int].

Objects​

Object types can be specified using object { x string, y int, z optional double }.

Type Declarations​

New type aliases can be created using the type keyword:

type Book object {
  title string,
  author string,
  description optional string
};

type Library array[Book];

skill library/find_book($title string) object { book optional Book } {
  # ...
}

Spec​

<parameter-list> := "(" <parameter> { "," <parameter> } ")"
<parameter> := <$identifier> [ "optional" ] <parameter-type>
<parameter-type> :=
  "bool" |
  "int" |
  "double" |
  "string" |
  "isodate" |
  "docref" |
  "json"
  <table-type> |
  <object-type> |
  "any"

<table-type> := "table" "(" <table-column> { "," <table-column> } ")"
<table-column> := <identifier> [ "optional" ] <simple-type>
<simple-type> :=
  "int" |
  "double" |
  "string"

<object-type> := "table" "(" <table-column> { "," <table-column> } ")"
<object-field> := <identifier> [ "optional" ] <parameter-type>