ty_ree/
declaration.rs

1//! Declarations: types, impl blocks, imports, constants, and extern functions.
2
3use crate::expression::{Block, Expression};
4use crate::types::{GenericParameter, Type};
5
6/// A named, typed function parameter.
7#[derive(Clone, Debug)]
8pub struct Parameter {
9    /// Parameter name.
10    pub name: String,
11    /// Parameter type.
12    pub parameter_type: Type,
13}
14
15/// Fixed-arity or variadic parameter list.
16#[derive(Clone, Debug)]
17pub enum ParameterList {
18    /// Fixed number of parameters.
19    Fixed(Vec<Parameter>),
20    /// Variadic (last parameter repeats).
21    Variadic(Vec<Parameter>),
22}
23
24impl ParameterList {
25    /// Returns the parameter slice regardless of arity kind.
26    pub fn parameters(&self) -> &[Parameter] {
27        match self {
28            Self::Fixed(parameters) | Self::Variadic(parameters) => parameters,
29        }
30    }
31}
32
33/// Makes a type callable: `impl Type -> R { body }`.
34///
35/// Constructing the type auto-evaluates the body.
36/// Each type has at most one impl block.
37#[derive(Clone, Debug)]
38pub struct ImplBlock {
39    /// Generic type/const parameters.
40    pub generic_parameters: Vec<GenericParameter>,
41    /// The type being made callable.
42    pub target_type: Type,
43    /// Return type and body.
44    pub callable: Callable,
45    /// Whether this impl is evaluated at compile time (`const fn`).
46    pub const_fn: bool,
47}
48
49/// Return type and body of a callable impl.
50#[derive(Clone, Debug)]
51pub struct Callable {
52    /// Return type of the callable.
53    pub return_type: Type,
54    /// Body executed on call.
55    pub body: Block,
56    /// Original parameter names when desugared from `fn`.
57    /// If present, the body uses these directly instead of `it.field`.
58    pub parameters: Option<Vec<Parameter>>,
59}
60
61/// Foreign function declaration (`extern fn`).
62#[derive(Clone, Debug)]
63pub struct ExternFunction {
64    /// Symbol name.
65    pub name: String,
66    /// Parameter list (may be variadic).
67    pub parameters: ParameterList,
68    /// Return type.
69    pub return_type: Type,
70}
71
72/// A newtype declaration (`type Name = Inner`).
73#[derive(Clone, Debug)]
74pub struct Newtype {
75    /// Type name.
76    pub name: String,
77    /// Generic type/const parameters.
78    pub generic_parameters: Vec<GenericParameter>,
79    /// Underlying wrapped type.
80    pub inner_type: Type,
81    /// Whether the type has external linkage.
82    pub public: bool,
83}
84
85/// A compile-time constant declaration.
86#[derive(Clone, Debug)]
87pub struct Constant {
88    /// Constant name.
89    pub name: String,
90    /// Type of the constant.
91    pub constant_type: Type,
92    /// Constant value expression.
93    pub value: Expression,
94    /// Whether the constant has external linkage.
95    pub public: bool,
96}
97
98/// A top-level declaration.
99#[derive(Clone, Debug)]
100pub enum Declaration {
101    /// Newtype declaration.
102    Type(Newtype),
103    /// Impl block making a type callable.
104    Impl(ImplBlock),
105    /// Foreign function import.
106    Extern(ExternFunction),
107    /// Compile-time constant.
108    Constant(Constant),
109    /// Module import by path.
110    Import(String),
111}
112
113/// A module is a sequence of declarations.
114pub type Module = Vec<Declaration>;
ty_ree/declaration.rs

ty_ree/
declaration.rs
