From 8b67c4d59c943cf26db1d3aa6839639ba9c2ba71 Mon Sep 17 00:00:00 2001
From: Kai-Philipp Nosper <kai-philipp.nosper@stud.h-da.de>
Date: Fri, 4 Feb 2022 17:30:23 +0100
Subject: [PATCH] Implement block scopes (code inside braces)

- Putting code in between braces will create a new scope
---
 src/ast.rs          | 1 +
 src/astoptimizer.rs | 1 +
 src/interpreter.rs  | 4 ++++
 src/parser.rs       | 8 ++++++++
 4 files changed, 14 insertions(+)

diff --git a/src/ast.rs b/src/ast.rs
index da3adc4..cccdf1d 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -113,6 +113,7 @@ pub struct If {
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub enum Statement {
     Expr(Expression),
+    Block(BlockScope),
     Loop(Loop),
     If(If),
     Print(Expression),
diff --git a/src/astoptimizer.rs b/src/astoptimizer.rs
index 39775a5..84bf5e5 100644
--- a/src/astoptimizer.rs
+++ b/src/astoptimizer.rs
@@ -18,6 +18,7 @@ impl SimpleAstOptimizer {
         for stmt in block {
             match stmt {
                 Statement::Expr(expr) => Self::optimize_expr(expr),
+                Statement::Block(block) => Self::optimize_block(block),
                 Statement::Loop(Loop {
                     condition,
                     advancement,
diff --git a/src/interpreter.rs b/src/interpreter.rs
index 0096a14..88327ca 100644
--- a/src/interpreter.rs
+++ b/src/interpreter.rs
@@ -78,6 +78,10 @@ impl Interpreter {
                     self.resolve_expr(expr);
                 }
 
+                Statement::Block(block) => {
+                    self.run_block(block);
+                }
+
                 Statement::Loop(looop) => {
                     // loop runs as long condition != 0
                     loop {
diff --git a/src/parser.rs b/src/parser.rs
index 3391209..7ab2892 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -50,6 +50,14 @@ impl<T: Iterator<Item = Token>> Parser<T> {
                 }
                 Token::EoF | Token::RBraces => break,
 
+                Token::LBraces => {
+                    self.next();
+                    prog.push(Statement::Block(self.parse_scoped_block()));
+                    if !matches!(self.next(), Token::RBraces) {
+                        panic!("Error parsing block: Expectected closing braces '}}'");
+                    }
+                }
+
                 // By default try to lex a statement
                 _ => prog.push(self.parse_stmt()),
             }