Add expressions

src/ast/expression/expression_node.rs

@@ -120,6 +120,7 @@ pub enum Literal {
 	Int(i32),
 	Float(f32),
 	Bool(bool),
+	Nil
 }
 
 pub struct BinaryExpr {

src/ast/expression/expression_parser.rs

@@ -102,6 +102,7 @@ impl<'a, T: Iterator<Item = token::Token<'a>>> Parser<'a, T> {
 				TokenType::Int(i) => ExpressionNode::Literal(Literal::Int(i)),
 				TokenType::String(i) => ExpressionNode::Literal(Literal::String(i)),
 				TokenType::Float(f) => ExpressionNode::Literal(Literal::Float(f)),
+				TokenType::Nil => ExpressionNode::Literal(Literal::Nil),
 				TokenType::LeftParen => {
 					let expr = self.expression()?;
 					let group = GroupingExpr::new(Box::new(expr));

src/ast/statement/statement_node.rs

@@ -7,8 +7,19 @@ pub enum Statement {
 	Print(PrintStatement),
 }
 
+macro_rules! all_variants {
+	($expr:expr, $val_name:ident => $expr_arm:expr) => {
+		{
+		use match_any::match_any;
+		use $crate::ast::statement::statement_node::*;
+		match_any!($expr, Statement::Expression($val_name) | Statement::Print($val_name) => $expr_arm)
+		}
+	};
+}
+pub(crate) use all_variants;
+
 #[derive(Debug)]
-pub struct ExpressionStatement(ExpressionNode);
+pub struct ExpressionStatement(pub ExpressionNode);
 impl ExpressionStatement {
 	pub fn new(expr: ExpressionNode) -> Self {
 		Self(expr)
@@ -16,7 +27,7 @@ impl ExpressionStatement {
 }
 
 #[derive(Debug)]
-pub struct PrintStatement(ExpressionNode);
+pub struct PrintStatement(pub ExpressionNode);
 impl PrintStatement {
 	pub fn new(expr: ExpressionNode) -> Self {
 		Self(expr)

src/interpreter/ast_walker/mod.rs

@@ -1,4 +1,5 @@
 mod expression_interpreter;
+mod statement_interpreter;
 pub use super::{error::RuntimeError, types};
 use super::types::Value;
 

src/interpreter/ast_walker/statement_interpreter.rs

@@ -0,0 +1,26 @@
+use super::{RuntimeError, types::Value};
+use super::Interpret;
+use crate::ast::statement::statement_node;
+
+
+
+impl Interpret for statement_node::Statement {
+	fn interpret(&self) -> Result<Value, RuntimeError> {
+		statement_node::all_variants!(self, n => n.interpret())
+	}
+}
+
+
+impl Interpret for statement_node::PrintStatement {
+    fn interpret(&self) -> Result<Value, RuntimeError> {
+		let res = self.0.interpret()?;
+		println!("{:?}", res);
+		Ok(res)
+    }
+}
+
+impl Interpret for statement_node::ExpressionStatement {
+    fn interpret(&self) -> Result<Value, RuntimeError> {
+		self.0.interpret()
+    }
+}

src/interpreter/environment.rs

@@ -0,0 +1,3 @@
+struct Environment {
+
+}

src/interpreter/mod.rs

@@ -1,3 +1,4 @@
 pub mod ast_walker;
 pub mod types;
 pub mod error;
+mod environment;

src/interpreter/types.rs

@@ -6,7 +6,7 @@ pub enum Value {
 	Int(i32),
 	Float(f32),
 	Bool(bool),
-	Null,
+	Nil,
 	// TODO: create a cow(not rust cow) string instead of cloning a normal string
 	String(String),
 }
@@ -14,14 +14,15 @@ pub enum Value {
 impl From<expression_node::Literal> for Value {
 	fn from(l: expression_node::Literal) -> Self {
 		match_any::match_any!(l,
-			expression_node::Literal::Int(v) | expression_node::Literal::Bool(v) | expression_node::Literal::Float(v) | expression_node::Literal::String(v) => v.into()
+			expression_node::Literal::Int(v) | expression_node::Literal::Bool(v) | expression_node::Literal::Float(v) | expression_node::Literal::String(v) => v.into(),
+			expression_node::Literal::Nil => Self::Nil
 		)
 	}
 }
 
 impl Default for Value {
 	fn default() -> Self {
-		Self::Null
+		Self::Nil
 	}
 }
 

src/lib.rs

@@ -23,12 +23,11 @@ pub fn parse(tokens: Vec<Token>) -> ParseAllResult {
 }
 
 pub fn exec(nodes: Vec<Statement>) -> Result<Value, RuntimeError> {
-	todo!();
-	/*
+	let mut last_res = Value::Nil;
 	for statement in nodes {
-		//statement.interpret()?;
+		last_res = statement.interpret()?;
 	}
-	*/
+	Ok(last_res)
 }
 
 pub fn run(code: &str) -> Result<Value, run::Error> {

test.lox

@@ -1 +1,5 @@
 1 == 1;
+1 == 2;
+print 1;
+print 2;
+nil;