From 3edbca51d5429416fd9b0cc8716e2db58fdb5b20 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Fri, 18 Jun 2021 20:28:53 +0200
Subject: [PATCH] Implemented read in Parser

---
 src/ast.rs       |  1 +
 src/interpret.rs |  1 +
 src/lexer.rs     |  4 ++++
 src/parser.rs    | 12 ++++++++++++
 4 files changed, 18 insertions(+)

diff --git a/src/ast.rs b/src/ast.rs
index 835e679..f84c47a 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -73,6 +73,7 @@ pub enum StmtKind {
         args: Vec<Expr>,
     },
     Print(Expr),
+    Read(Iden),
     Melo(Iden),
     Rlyeh,
     Rickroll,
diff --git a/src/interpret.rs b/src/interpret.rs
index 43d48d9..29466ec 100644
--- a/src/interpret.rs
+++ b/src/interpret.rs
@@ -280,6 +280,7 @@ impl ExecEnv {
                     .write_all(include_str!("rickroll").as_bytes())
                     .expect("Failed to write to stdout");
             }
+            StmtKind::Read(_) => todo!(),
         }
 
         Ok(HaltStatus::Finished)
diff --git a/src/lexer.rs b/src/lexer.rs
index 3f686c0..7632386 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -86,6 +86,10 @@ pub enum Token {
     #[token("print")]
     Print,
 
+    /// Read input into preceding variable
+    #[token("read")]
+    Read,
+
     /// Ban the following variable from ever being used again
     #[token("melo")]
     Melo,
diff --git a/src/parser.rs b/src/parser.rs
index 893f44b..90d86bc 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -318,6 +318,18 @@ impl<'source> Parser<'source> {
                         };
                     }
                 }
+
+                // Read input
+                Token::Read => {
+                    if let Some(Expr {
+                        kind: ExprKind::Variable(iden),
+                        span,
+                    }) = buf
+                    {
+                        break self.semi_terminated(StmtKind::Read(Iden::new(iden, span)))?;
+                    }
+                }
+
                 t => buf = Some(self.parse_expr(t, &mut buf)?),
             }
         };