From f1a468aebca9219672b29a49a13f05ccd6e85691 Mon Sep 17 00:00:00 2001
From: Garritt McCune <glmccune@gmail.com>
Date: Mon, 14 Feb 2022 19:38:49 +0000
Subject: [PATCH] Added support for string literals.

---
 lox.c     |  2 +-
 scanner.c | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/lox.c b/lox.c
index 8881c00..e8a598d 100644
--- a/lox.c
+++ b/lox.c
@@ -25,7 +25,7 @@ void Print(TokenList* list) {
 
     for(int i = 0; i < list->size; i++) {
         if (list->tokens[i]->type == EndOF) {
-            printf("EOF\n");\
+            printf("[Line %d] EOF\n", list->tokens[i]->line);\
             return;
         }
 
diff --git a/scanner.c b/scanner.c
index 7cee204..d685a0d 100644
--- a/scanner.c
+++ b/scanner.c
@@ -17,6 +17,7 @@ TokenList* CreateList(void);
 int AddTokenToList(TokenType, const char*, int, TokenList*);
 int Match(char);
 char Peek(void);
+void ParseString(TokenList *);
 
 TokenList* ScanTokens(const char* source) {
     if (!source) return NULL;
@@ -143,6 +144,18 @@ void ScanToken(TokenList* tokens) {
         if (Match('=')) AddTokenToList(Bang_Equal, "!=", 2, tokens);
         else AddTokenToList(Bang, c, 1, tokens);
         break;
+    case '=':
+        if (Match('=')) AddTokenToList(Equal_Equal, "==", 2, tokens);
+        else AddTokenToList(Equal, c, 1, tokens);
+        break;
+    case '<':
+        if (Match('=')) AddTokenToList(Less_Equal, "<=", 2, tokens);
+        else AddTokenToList(Less, c, 1, tokens);
+        break;
+    case '>':
+        if (Match('=')) AddTokenToList(Greater_Equal, ">=", 2, tokens);
+        else AddTokenToList(Greater, c, 1, tokens);
+        break;
     case '/':
         if (Match('/')) {
             while(Peek() != '\n' && !IsAtEnd()) Advance();
@@ -151,6 +164,9 @@ void ScanToken(TokenList* tokens) {
             AddTokenToList(Slash, c, 1, tokens);
         }
         break;
+    case '"':
+        ParseString(tokens);
+        break;
     case ' ':
     case '\r':
     case '\t':
@@ -185,4 +201,22 @@ char Peek() {
     if (IsAtEnd()) return '\0';
 
     return source_code[current];
+}
+
+void ParseString(TokenList *list) {
+    start = current;    //The start is currently pointing to the first double quote so we need to move it
+                        //to the next (first character) of the string literal.
+    while(Peek() != '"' && !IsAtEnd()) {
+        if (Peek() == '\n') line++;
+        Advance();
+    }
+
+    if (IsAtEnd()) {
+        fprintf(stderr, "Unterminated string.\n");
+        return;
+    }
+
+    AddTokenToList(String, &source_code[start], current - start, list);
+
+    Advance(); // The closing ".
 }
\ No newline at end of file