Structures pour représenter une expression et affichage d'un AST.

src/main.rs

@@ -1,6 +1,7 @@
 use std::env;
 use std::process;
-use crate::expr::Expr;
+use crate::expr::{Binary, Expr, Grouping, Literal, Unary, Visitable};
+use crate::expr::Expr::LiteralExpr;
 
 mod rlox_interpreter;
 mod scanner;
@@ -9,6 +10,8 @@ mod token_type;
 mod expr;
 
 use crate::rlox_interpreter::RLoxInterpreter;
+use crate::token::Token;
+use crate::token_type::TokenType;
 
 // Exit codes from #include <sysexits.h>
 const EX_OK: i32 = 0;
@@ -18,6 +21,8 @@ const EX_USAGE : i32 = 66;
 fn main() {
     let args: Vec<String> = env::args().collect();
 
+    essai_visitor();
+
     let exit_code = match args.len() {
         1 => { RLoxInterpreter::new().run_prompt() } ,
         2 => { RLoxInterpreter::new().run_file(&args[1]) },
@@ -30,6 +35,30 @@ fn main() {
     process::exit(exit_code);
 }
 
+fn essai_visitor() {
+    let expression = Expr::BinaryExpr(Binary {
+        left: Box::new(Expr::UnaryExpr( Unary {
+            operator: Token {
+                token_type: TokenType::Minus,
+                lexeme: String::from("-"),
+                line: 0,
+                literal: String::from("-")
+            },
+            right: Box::new(Expr::LiteralExpr(Literal::LiteralNumber(123.0)))
+        })),
+        operator: Token {
+            token_type: TokenType::Star,
+            lexeme: String::from("*"),
+            line: 0,
+            literal: String::from("*")
+        },
+        right: Box::new(Expr::GroupingExpr ( Grouping {
+                expression: Box::new(LiteralExpr(Literal::LiteralNumber(123.0)))
+        }))
+    });
+
+    expression.visit();
+}
 
 
 // Implémentations de référence :