tseeker-pub/rust-crafting-interpreters-part-1
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Interpreter - Create and pass the environment when evaluating

Browse source
This commit is contained in:
Emmanuel BENOîT 2022-12-31 16:01:47 +01:00
parent 8b44af08ba
commit 90557e6600
1 changed files with 19 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

34
src/interpreter/interpretable.rs
View file

@ -5,14 +5,17 @@ use crate::{
tokens::{Token, TokenType},
};
use super::Environment;
/// An Interpretable can be evaluated and will return a value.
pub trait Interpretable {
fn interprete(&self) -> Result<Value, InterpreterError>;
fn interprete(&self, environment: &mut Environment) -> Result<Value, InterpreterError>;
}
/// Evaluate an interpretable, returning its value.
pub fn evaluate(err_hdl: &mut ErrorHandler, ast: &dyn Interpretable) -> Option<Value> {
match ast.interprete() {
let mut env = Environment::default();
match ast.interprete(&mut env) {
Ok(v) => Some(v),
Err(e) => {
e.report(err_hdl);
@ -26,9 +29,9 @@ pub fn evaluate(err_hdl: &mut ErrorHandler, ast: &dyn Interpretable) -> Option<V
* ----------------------------- */
impl Interpretable for ast::ProgramNode {
fn interprete(&self) -> Result<Value, InterpreterError> {
fn interprete(&self, environment: &mut Environment) -> Result<Value, InterpreterError> {
for stmt in self.0.iter() {
stmt.interprete()?;
stmt.interprete(environment)?;
}
Ok(Value::Nil)
}
@ -39,11 +42,11 @@ impl Interpretable for ast::ProgramNode {
* ------------------------------- */
impl Interpretable for ast::StmtNode {
fn interprete(&self) -> Result<Value, InterpreterError> {
fn interprete(&self, environment: &mut Environment) -> Result<Value, InterpreterError> {
match self {
ast::StmtNode::Expression(expr) => expr.interprete(),
ast::StmtNode::Expression(expr) => expr.interprete(environment),
ast::StmtNode::Print(expr) => {
let value = expr.interprete()?;
let value = expr.interprete(environment)?;
let output = match value {
Value::Nil => String::from("nil"),
Value::Boolean(true) => String::from("true"),
@ -63,15 +66,15 @@ impl Interpretable for ast::StmtNode {
* -------------------------------- */
impl Interpretable for ast::ExprNode {
fn interprete(&self) -> Result<Value, InterpreterError> {
fn interprete(&self, environment: &mut Environment) -> Result<Value, InterpreterError> {
match self {
ast::ExprNode::Binary {
left,
operator,
right,
} => self.on_binary(left, operator, right),
ast::ExprNode::Unary { operator, right } => self.on_unary(operator, right),
ast::ExprNode::Grouping { expression } => expression.interprete(),
} => self.on_binary(environment, left, operator, right),
ast::ExprNode::Unary { operator, right } => self.on_unary(environment, operator, right),
ast::ExprNode::Grouping { expression } => expression.interprete(environment),
ast::ExprNode::Litteral { value } => self.on_litteral(value),
}
}
@ -81,12 +84,13 @@ impl ast::ExprNode {
/// Evaluate a binary operator.
fn on_binary(
&self,
environment: &mut Environment,
left: &ast::ExprNode,
operator: &Token,
right: &ast::ExprNode,
) -> Result<Value, InterpreterError> {
let left_value = left.interprete()?;
let right_value = right.interprete()?;
let left_value = left.interprete(environment)?;
let right_value = right.interprete(environment)?;
match operator.token_type {
TokenType::Plus => match (left_value, right_value) {
(Value::Number(a), Value::Number(b)) => Ok(Value::Number(a + b)),
@ -147,8 +151,8 @@ impl ast::ExprNode {
}
/// Evaluate an unary operator.
fn on_unary(&self, operator: &Token, right: &ast::ExprNode) -> Result<Value, InterpreterError> {
let right_value = right.interprete()?;
fn on_unary(&self, environment: &mut Environment, operator: &Token, right: &ast::ExprNode) -> Result<Value, InterpreterError> {
let right_value = right.interprete(environment)?;
match operator.token_type {
TokenType::Minus => {
if let Value::Number(n) = right_value {