forked from AbleScript/ablescript
147 lines
2.9 KiB
Rust
147 lines
2.9 KiB
Rust
//! AbleScript's Abstract Syntax tree
|
|
//!
|
|
//! Statements are the type which is AST made of, as they
|
|
//! express an effect.
|
|
//!
|
|
//! Expressions are just operations and they cannot be
|
|
//! used as statements. Functions in AbleScript are in fact
|
|
//! just plain subroutines and they do not return any value,
|
|
//! so their calls are statements.
|
|
|
|
use crate::variables::Value;
|
|
|
|
type Span = std::ops::Range<usize>;
|
|
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub struct Iden {
|
|
pub iden: String,
|
|
pub span: Span,
|
|
}
|
|
|
|
impl Iden {
|
|
pub fn new(iden: String, span: Span) -> Self {
|
|
Self { iden, span }
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub struct Block {
|
|
pub block: Vec<Stmt>,
|
|
}
|
|
|
|
/// A syntactic unit expressing an effect.
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub struct Stmt {
|
|
pub kind: StmtKind,
|
|
pub span: Span,
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub enum StmtKind {
|
|
// Control flow
|
|
If {
|
|
cond: Expr,
|
|
body: Block,
|
|
},
|
|
Loop {
|
|
body: Block,
|
|
},
|
|
Break,
|
|
HopBack,
|
|
|
|
Var {
|
|
iden: Iden,
|
|
init: Option<Expr>,
|
|
},
|
|
Assign {
|
|
iden: Iden,
|
|
value: Expr,
|
|
},
|
|
|
|
Functio {
|
|
iden: Iden,
|
|
params: Vec<Iden>,
|
|
body: Block,
|
|
},
|
|
BfFunctio {
|
|
iden: Iden,
|
|
tape_len: Option<Expr>,
|
|
code: Vec<u8>,
|
|
},
|
|
Call {
|
|
iden: Iden,
|
|
args: Vec<Expr>,
|
|
},
|
|
Print(Expr),
|
|
Read(Iden),
|
|
Melo(Iden),
|
|
Rlyeh,
|
|
Rickroll,
|
|
}
|
|
|
|
impl Stmt {
|
|
pub fn new(kind: StmtKind, span: Span) -> Self {
|
|
Self { kind, span }
|
|
}
|
|
}
|
|
|
|
/// Expression is parse unit which do not cause any effect,
|
|
/// like math and logical operations or values.
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub struct Expr {
|
|
pub kind: ExprKind,
|
|
pub span: Span,
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub enum ExprKind {
|
|
BinOp {
|
|
lhs: Box<Expr>,
|
|
rhs: Box<Expr>,
|
|
kind: BinOpKind,
|
|
},
|
|
Not(Box<Expr>),
|
|
Literal(Value),
|
|
Variable(String),
|
|
}
|
|
|
|
impl Expr {
|
|
pub fn new(kind: ExprKind, span: Span) -> Self {
|
|
Self { kind, span }
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Clone)]
|
|
pub enum BinOpKind {
|
|
Add,
|
|
Subtract,
|
|
Multiply,
|
|
Divide,
|
|
Greater,
|
|
Less,
|
|
Equal,
|
|
NotEqual,
|
|
And,
|
|
Or,
|
|
}
|
|
|
|
impl BinOpKind {
|
|
pub fn from_token(t: crate::lexer::Token) -> Result<Self, crate::error::ErrorKind> {
|
|
use crate::lexer::Token;
|
|
|
|
match t {
|
|
Token::Plus => Ok(Self::Add),
|
|
Token::Minus => Ok(Self::Subtract),
|
|
Token::Star => Ok(Self::Multiply),
|
|
Token::FwdSlash => Ok(Self::Divide),
|
|
Token::GreaterThan => Ok(Self::Greater),
|
|
Token::LessThan => Ok(Self::Less),
|
|
Token::EqualEqual => Ok(Self::Equal),
|
|
Token::NotEqual => Ok(Self::NotEqual),
|
|
Token::And => Ok(Self::And),
|
|
Token::Or => Ok(Self::Or),
|
|
t => Err(crate::error::ErrorKind::UnexpectedToken(t)),
|
|
}
|
|
}
|
|
}
|