diff --git a/src/tokens.cpp b/src/tokens.cpp
index d6a0642..3b64209 100644
--- a/src/tokens.cpp
+++ b/src/tokens.cpp
@@ -128,7 +128,9 @@ namespace token {
         uint32_t line = 0;
         uint32_t line_start = 0;
 
-        for (int i = 0; i < static_cast<int>(text.length());) {
+        int text_length = static_cast<int>(text.length());
+
+        for (int i = 0; i < text_length;) {
             Position position{ line, i - line_start };
             Metadata meta{ position, position, filename };
 
@@ -138,6 +140,7 @@ namespace token {
                 std::string content{};
                 do {
                     content += c;
+                    if ((i + 1) >= text_length) break;
                     c = text[++i];
                 } while (std::isdigit(c));
                 tokens.push_back(token::Token{ token::Type::LiteralInt, content, meta + content.size() });
@@ -147,6 +150,7 @@ namespace token {
                 c = text[++i]; // Skip initial "
                 do {
                     content += c;
+                    if ((i + 1) >= text_length) break;
                     c = text[++i];
                 } while (c != '\"');
                 i++; // Skip second "
@@ -156,6 +160,7 @@ namespace token {
                 std::string content{};
                 do {
                     content += c;
+                    if ((i + 1) >= text_length) break;
                     c = text[++i];
                 } while (std::isalnum(c));
 
@@ -179,6 +184,7 @@ namespace token {
                         line_start = i + 1;
                     }
                     content += c;
+                    if ((i + 1) >= text_length) break;
                     c = text[++i];
                 } while (iswhitespace(c));
                 // tokens.push_back(token::Token{ token::Type::Whitespace, content });