a few more things

src/parser/parser.rs

@@ -1,46 +1,6 @@
 use super::types::*;
 use crate::ast;
 
-fn parse_expr(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
-    todo!()
-}
-
-fn parse_simple_expr(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
-    tokens.one_of(vec![
-        |t| t.between(Token::OpenParen, Token::CloseParen, parse_expr),
-        parse_number,
-        |_| Err(Error::UnexpectedEndOfInput),
-    ])
-}
-
-fn parse_string(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
-    {
-        if let Some(LocatedToken {
-            token: Token::String(string),
-            ..
-        }) = tokens.next_if(Token::String("".into()))
-        {
-            Ok(Some(ast::Expr::Value(ast::Value::String(string))))
-        } else {
-            Ok(None)
-        }
-    }
-}
-
-fn parse_number(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
-    {
-        if let Some(LocatedToken {
-            token: Token::Number(number),
-            ..
-        }) = tokens.next_if(Token::Number(0))
-        {
-            Ok(Some(ast::Expr::Value(ast::Value::Int(number.into()))))
-        } else {
-            Ok(None)
-        }
-    }
-}
-
 fn parse_definition(tokens: &mut Tokens) -> Result<ast::Definition, Error> {
     if let Some(start) = tokens.next_if(Token::Let) {
         if let Some(LocatedToken {
@@ -76,3 +36,82 @@ fn parse_definition(tokens: &mut Tokens) -> Result<ast::Definition, Error> {
         Err(Error::UnexpectedEndOfInput)
     }
 }
+
+fn parse_expr(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    parse_simple_expr(tokens)
+}
+
+fn parse_simple_expr(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    tokens.one_of(vec![
+        |t| t.between(Token::OpenParen, Token::CloseParen, parse_expr),
+        parse_identifier,
+        parse_number,
+        parse_string,
+        parse_bool,
+    ])
+}
+
+fn parse_string(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    {
+        if let Some(LocatedToken {
+            token: Token::String(string),
+            ..
+        }) = tokens.next_if(Token::String("".into()))
+        {
+            Ok(Some(ast::Expr::Value(ast::Value::String(string))))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+fn parse_number(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    {
+        if let Some(LocatedToken {
+            token: Token::Number(number),
+            ..
+        }) = tokens.next_if(Token::Number(0))
+        {
+            Ok(Some(ast::Expr::Value(ast::Value::Int(number.into()))))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+fn parse_identifier(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    {
+        if let Some(LocatedToken {
+            token: Token::Identifier(string),
+            ..
+        }) = tokens.next_if(Token::String("".into()))
+        {
+            Ok(Some(ast::Expr::Var(ast::Name(string))))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+fn parse_bool(tokens: &mut Tokens) -> ParseResult<ast::Expr> {
+    tokens.one_of(vec![
+        |t| {
+            Ok({
+                if let Some(_) = t.next_if(Token::True) {
+                    Some(ast::Expr::Value(ast::Value::Boolean(true)))
+                } else {
+                    None
+                }
+            })
+        },
+        |t| {
+            Ok({
+                if let Some(_) = t.next_if(Token::False) {
+                    Some(ast::Expr::Value(ast::Value::Boolean(false)))
+                } else {
+                    None
+                }
+            })
+        },
+    ])
+}

src/parser/scanner.rs

@@ -137,6 +137,8 @@ fn scan(source: String) -> Vec<LocatedToken> {
                             "fn" => Token::Fn,
                             "let" => Token::Let,
                             "return" => Token::Return,
+                            "true" => Token::True,
+                            "false" => Token::False,
                             _ => Token::Identifier(str),
                         },
                     });

src/parser/types.rs

@@ -21,6 +21,8 @@ pub enum Token {
     Comma,
     Semicolon,
     Colon,
+    True,
+    False,
     Number(u32),
     String(String),
     Identifier(String),