Changed the grammar to allow bare top-level expressions only in REPL.

1 files changed, 20 insertions, 7 deletions

diff --git a/parser/src/main/java/lv/enes/orang/parser/Parser.java b/parser/src/main/java/lv/enes/orang/parser/Parser.java
index 3a2e931..9103123 100644
--- a/parser/src/main/java/lv/enes/orang/parser/Parser.java
+++ b/parser/src/main/java/lv/enes/orang/parser/Parser.java
@@ -27,9 +27,9 @@ public class Parser {
                 return parser.parseProgram();
         }
 
-        public static Program parseProgram(String in) throws ParserException {
+        public static Program parseReplProgram(String in) throws ParserException {
                 var parser = new Parser(in);
-                return parser.parseProgram();
+                return parser.parseReplProgram();
         }
 
         private final PeekableStream<Token> input;
@@ -59,6 +59,15 @@ public class Parser {
                 return new Program(Collections.unmodifiableList(statements));
         }
 
+        public Program parseReplProgram() throws ParserException {
+                var statements = new ArrayList<Statement>();
+                while (!maybeConsumeToken(Token.Type.EOF)) {
+                        statements.add(parseReplLine());
+                        maybeConsumeToken(Token.Type.SEMICOLON);
+                }
+                return new Program(Collections.unmodifiableList(statements));
+        }
+
         private static boolean isNotBinaryOp(Token token) {
                 return switch (token.type()) {
                         case ASTERISK, SLASH, PLUS, MINUS, QUESTION_EQUAL, SLASH_EQUAL, GREATER, GREATER_EQUAL, LESS, LESS_EQUAL
@@ -275,6 +284,14 @@ public class Parser {
                 return new LetInExpression(Collections.unmodifiableList(bindings), body);
         }
 
+        private Statement parseReplLine() throws ParserException {
+                if (input.peek().type() == Token.Type.DEF) {
+                        return parseStatement();
+                } else {
+                        return new ExpressionStatement(parseExpression());
+                }
+        }
+
         private Expression parseSimpleExpression() throws ParserException {
                 return switch (input.peek().type()) {
                         case PAREN_LEFT -> {
@@ -307,11 +324,7 @@ public class Parser {
         }
 
         private Statement parseStatement() throws ParserException {
-                if (input.peek().type() == Token.Type.DEF) {
-                        return parseDefinition();
-                } else {
-                        return new ExpressionStatement(parseExpression());
-                }
+                return parseDefinition();
         }
 
         private Expression parseString() throws ParserException {