diff --git a/inc/format.h b/inc/format.h
index 690c3e7..96596da 100644
--- a/inc/format.h
+++ b/inc/format.h
@@ -20,7 +20,7 @@ namespace detail {
 
 
 template <ConstString s>
-constexpr int get_output_len() {
+constexpr inline int get_output_len() {
     constexpr auto parse_result = parse_string<s>();
     static_assert(parse_result.is_valid, "Syntax error in format string");
 
@@ -28,7 +28,7 @@ constexpr int get_output_len() {
 }
 
 template <fmt_node_t fmt_node, typename T>
-constexpr void check_fmt_params() {
+constexpr inline void check_fmt_params() {
     static_assert(fmt_node.length > fmt_node.precision + 1,
                   "Insufficient length for desired precision");
 }
@@ -40,19 +40,21 @@ constexpr void check_fmt_params() {
  *
  */
 
-
+// TODO: Error handling
 template <std::integral arg_t>
-constexpr void format_arg(char* dest, fmt_data_t fmt_data, arg_t arg) {
+constexpr inline void format_arg(char* dest, fmt_data_t fmt_data, arg_t arg) {
+//    constexpr auto error_array = get_init_array<fmt_data.length>('f');
+
     detail::format_integral(dest, arg, fmt_data);
 };
-
+// TODO: Error handling
 template <std::floating_point arg_t>
-constexpr void format_arg(char* dest, fmt_data_t fmt_data, arg_t) {
+constexpr inline void format_arg(char* dest, fmt_data_t fmt_data, arg_t) {
     *(dest) = 'f';
     *(dest + fmt_data.length - fmt_data.precision - 1) = '.';
 };
 // TODO: Error handling
-constexpr void format_arg(char* dest, fmt_data_t fmt_data, const char* arg) {
+constexpr inline void format_arg(char* dest, fmt_data_t fmt_data, const char* arg) {
     const std::size_t len = const_strlen(arg);
     if (len > fmt_data.length) return;
 
@@ -68,20 +70,21 @@ constexpr void format_arg(char* dest, fmt_data_t fmt_data, const char* arg) {
 };
 
 
+// End of recursion
 template <auto ast>
-constexpr void format_args(char*) {
+constexpr inline void format_args(char*) {
 }
 
 template <auto fmt_data_array, typename first_arg_t, typename... args_t>
-constexpr void format_args(char* dest, first_arg_t first_arg, args_t... args) {
+constexpr inline void format_args(char* dest, first_arg_t first_arg, args_t... args) {
     format_arg(dest + fmt_data_array[0].position, fmt_data_array[0], first_arg);
     format_args<drop_first(fmt_data_array)>(dest, args...);
 }
 
 
 template <auto ast>
-consteval std::array<char, get_ast_output_len<ast>()> get_preproc_string() {
-    auto result = get_zero_array<get_ast_output_len<ast>()>();
+consteval inline std::array<char, get_ast_output_len<ast>()> get_preproc_string() {
+    auto result = get_init_array<get_ast_output_len<ast>()>('0');
 
     int i = 0;
 
@@ -107,7 +110,7 @@ consteval std::array<char, get_ast_output_len<ast>()> get_preproc_string() {
 
 
 template <detail::ConstString s, typename... args_t>
-constexpr auto format(args_t... args) {
+constexpr inline auto format(args_t... args) {
     constexpr auto ast      = detail::parse_string<s>().value;
     constexpr auto fmt_data = detail::get_fmt_data<ast>();
 
diff --git a/inc/format_impl.h b/inc/format_impl.h
index 68f3de7..c1e4216 100644
--- a/inc/format_impl.h
+++ b/inc/format_impl.h
@@ -47,9 +47,6 @@ constexpr inline void copy2(char* dst, const char* src) {
 
 template <typename UInt>
 constexpr inline void format_decimal(char* out, UInt value, int size) {
-    // TODO: Error handling (Maybe calculate "ffff..." as a constant expression
-    //       and then set the out pointer with a branchless statement)
-
     out += size;
     while (value >= 100) {
         out -= 2;
diff --git a/inc/parse.h b/inc/parse.h
index 6ca6af3..f1da473 100644
--- a/inc/parse.h
+++ b/inc/parse.h
@@ -48,7 +48,7 @@ namespace detail {
 
 
 template <ConstString s>
-constexpr unsigned count_braces() {
+constexpr inline unsigned count_braces() {
     unsigned result = 0;
 
     for (unsigned i = 0; i < s.size(); ++i) {
@@ -59,7 +59,7 @@ constexpr unsigned count_braces() {
 }
 
 template <ConstString s>
-constexpr unsigned strlen_braces() {
+constexpr inline unsigned strlen_braces() {
     unsigned result = 0;
 
     bool brace_open = false;
@@ -81,7 +81,7 @@ constexpr unsigned strlen_braces() {
 }
 
 template <ConstString s>
-constexpr int get_ast_len() {
+constexpr inline int get_ast_len() {
     return (s.size() - strlen_braces<s>() + count_braces<s>());
 }
 
@@ -94,13 +94,13 @@ constexpr int get_ast_len() {
 
 
 template <ConstString s>
-constexpr bool is_digit(unsigned i) {
+constexpr inline bool is_digit(unsigned i) {
     return (s[i] > 47) && (s[i] < 58);
 }
 
 
 template <ConstString s>
-constexpr parse_result_t<unsigned> parse_number(unsigned i) {
+constexpr inline parse_result_t<unsigned> parse_number(unsigned i) {
     unsigned number = 0;
 
     if (!is_digit<s>(i)) {
@@ -117,7 +117,7 @@ constexpr parse_result_t<unsigned> parse_number(unsigned i) {
 }
 
 template <ConstString s>
-constexpr parse_result_t<FormatType> parse_type(unsigned i) {
+constexpr inline parse_result_t<FormatType> parse_type(unsigned i) {
     switch (s[i]) {
         case 's':
             return {true, ++i, FormatType::s};
@@ -159,7 +159,7 @@ constexpr parse_result_t<FormatType> parse_type(unsigned i) {
 }
 
 template <ConstString s>
-constexpr parse_result_t<fmt_node_t> parse_fmt_string(unsigned i) {
+constexpr inline parse_result_t<fmt_node_t> parse_fmt_string(unsigned i) {
     fmt_node_t result;
 
     if (s[i] == '0') {
@@ -193,7 +193,7 @@ constexpr parse_result_t<fmt_node_t> parse_fmt_string(unsigned i) {
 }
 
 template <ConstString s>
-constexpr parse_result_t<fmt_node_t> parse_braces(unsigned i) {
+constexpr inline parse_result_t<fmt_node_t> parse_braces(unsigned i) {
     if (s[i] == '}') {
         ++i;
         return {true, i, {}};
@@ -214,7 +214,7 @@ constexpr parse_result_t<fmt_node_t> parse_braces(unsigned i) {
 }
 
 template <ConstString s>
-constexpr parse_result_t<string_result_t<get_ast_len<s>()>> parse_string() {
+constexpr inline parse_result_t<string_result_t<get_ast_len<s>()>> parse_string() {
     parse_result_t<string_result_t<get_ast_len<s>()>> result;
     result.is_valid = true;
 
diff --git a/inc/utility.h b/inc/utility.h
index 42a2697..86b2052 100644
--- a/inc/utility.h
+++ b/inc/utility.h
@@ -10,7 +10,7 @@
 namespace detail {
 
 
-constexpr std::size_t const_pow(std::size_t base, std::size_t pow) {
+constexpr inline std::size_t const_pow(std::size_t base, std::size_t pow) {
     if (pow == 0)
         return 1;
     else
@@ -18,34 +18,44 @@ constexpr std::size_t const_pow(std::size_t base, std::size_t pow) {
 }
 
 
+//template <std::size_t t_n>
+//constexpr std::array<char, t_n> get_zero_array() {
+//    std::array<char, t_n> result;
+//
+//    for (auto& c : result)
+//        c = '0';
+//
+//    return result;
+//}
+
 template <std::size_t t_n>
-constexpr std::array<char, t_n> get_zero_array() {
+constexpr inline std::array<char, t_n> get_init_array(char val) {
     std::array<char, t_n> result;
 
     for (auto& c : result)
-        c = '0';
+        c = val;
 
     return result;
 }
 
-template <fmt_node_t fmt_node>
-constexpr std::array<char, fmt_node.length> get_init_array() {
-    std::array<char, fmt_node.length> result;
-
-    if constexpr (fmt_node.has_zero_padding) {
-        for (auto& c : result)
-            c = '0';
-    } else {
-        for (auto& c : result)
-            c = ' ';
-    }
-
-    return result;
-}
+//template <fmt_node_t fmt_node>
+//constexpr std::array<char, fmt_node.length> get_init_array() {
+//    std::array<char, fmt_node.length> result;
+//
+//    if constexpr (fmt_node.has_zero_padding) {
+//        for (auto& c : result)
+//            c = '0';
+//    } else {
+//        for (auto& c : result)
+//            c = ' ';
+//    }
+//
+//    return result;
+//}
 
 
 template <auto ast>
-consteval std::size_t count_ast_format_nodes() {
+consteval inline std::size_t count_ast_format_nodes() {
     std::size_t result = 0;
 
     for (const auto& node : ast)
@@ -56,7 +66,7 @@ consteval std::size_t count_ast_format_nodes() {
 
 
 template <auto ast>
-consteval std::array<fmt_data_t, count_ast_format_nodes<ast>()> get_fmt_data() {
+consteval inline std::array<fmt_data_t, count_ast_format_nodes<ast>()> get_fmt_data() {
     std::array<fmt_data_t, count_ast_format_nodes<ast>()> result = {};
 
     std::size_t position = 0;
@@ -84,7 +94,7 @@ consteval std::array<fmt_data_t, count_ast_format_nodes<ast>()> get_fmt_data() {
 
 
 template <typename elem_t, std::size_t t_n>
-consteval std::array<elem_t, t_n - 1>
+consteval inline std::array<elem_t, t_n - 1>
 drop_first(std::array<elem_t, t_n> array) {
     static_assert(t_n > 0,
                   "Can't drop first element of array with no elements");
@@ -98,7 +108,7 @@ drop_first(std::array<elem_t, t_n> array) {
 
 
 template <auto t_ast>
-consteval int get_ast_output_len() {
+consteval inline int get_ast_output_len() {
     unsigned result = 0;
 
     for (const auto& ast_node : t_ast) {
@@ -111,7 +121,7 @@ consteval int get_ast_output_len() {
     return result;
 }
 
-constexpr std::size_t const_strlen(const char* arg) {
+constexpr inline  std::size_t const_strlen(const char* arg) {
     if (std::is_constant_evaluated()) {
         return *arg ? 1 + const_strlen(arg + 1) : 0;
     } else {