diff --git a/include/ss/converter.hpp b/include/ss/converter.hpp
index f2e0433..1d5af37 100644
--- a/include/ss/converter.hpp
+++ b/include/ss/converter.hpp
@@ -2,6 +2,7 @@
 #include "extract.hpp"
 #include "function_traits.hpp"
 #include "restrictions.hpp"
+#include "splitter.hpp"
 #include "type_traits.hpp"
 #include <string>
 #include <type_traits>
@@ -105,347 +106,6 @@ constexpr bool tied_class_v = tied_class<Ts...>::value;
 // the error can be set inside a string, or a bool
 enum class error_mode { error_string, error_bool };
 
-////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////
-
-///////////////////////////////////////////////////////////////////////////////
-template <char... Cs>
-struct matcher {
-private:
-    template <char X, char... Xs>
-    static bool match_impl(char c) {
-        if constexpr (sizeof...(Xs) != 0) {
-            return (c == X) || match_impl<Xs...>(c);
-        }
-        return (c == X);
-    }
-
-public:
-    static bool match(char c) {
-        return match_impl<Cs...>(c);
-    }
-    constexpr static bool enabled = true;
-};
-
-template <>
-class matcher<'\0'> {
-public:
-    constexpr static bool enabled = false;
-    static bool match(char c) = delete;
-};
-
-////////////////
-// is instance of
-////////////////
-
-template <typename T, template <char...> class Template>
-struct is_instance_of_char {
-    constexpr static bool value = false;
-};
-
-template <char... Ts, template <char...> class Template>
-struct is_instance_of_char<Template<Ts...>, Template> {
-    constexpr static bool value = true;
-};
-
-///////////////////////////////////////////////////
-
-template <char... Cs>
-struct quote : matcher<Cs...> {};
-
-template <char... Cs>
-struct trim : matcher<Cs...> {};
-
-template <char... Cs>
-struct escape : matcher<Cs...> {};
-
-/////////////////////////////////////////////////
-// -> type traits
-template <bool B, typename T, typename U>
-struct if_then_else;
-
-template <typename T, typename U>
-struct if_then_else<true, T, U> {
-    using type = T;
-};
-
-template <typename T, typename U>
-struct if_then_else<false, T, U> {
-    using type = U;
-};
-
-//////////////////////////////////////////////
-template <template <char...> class Matcher, typename... Ts>
-struct get_matcher;
-
-template <template <char...> class Matcher, typename T, typename... Ts>
-struct get_matcher<Matcher, T, Ts...> {
-    using type =
-        typename if_then_else<is_instance_of_char<T, Matcher>::value, T,
-                              typename get_matcher<Matcher, Ts...>::type>::type;
-};
-
-template <template <char...> class Matcher>
-struct get_matcher<Matcher> {
-    using type = Matcher<'\0'>;
-};
-
-///////////////////////////////////////////////
-// TODO add restriction
-template <typename... Ts>
-struct setup {
-    using quote = typename get_matcher<quote, Ts...>::type;
-    using trim = typename get_matcher<trim, Ts...>::type;
-    using escape = typename get_matcher<escape, Ts...>::type;
-};
-
-template <typename... Ts>
-struct setup<setup<Ts...>> : setup<Ts...> {};
-
-/////////////////////////////////////////////////////////////////////////////
-
-enum class State { finished, begin, reading, quoting };
-using range = std::pair<const char*, const char*>;
-
-using string_range = std::pair<const char*, const char*>;
-using split_input = std::vector<string_range>;
-
-template <typename... Ts>
-class splitter {
-    using Setup = setup<Ts...>;
-    using quote = typename Setup::quote;
-    using trim = typename Setup::trim;
-    using escape = typename Setup::escape;
-
-    bool match(const char* end_i, char delim) {
-        return *end_i == delim;
-    };
-
-    bool match(const char* end_i, const std::string& delim) {
-        return strncmp(end_i, delim.c_str(), delim.size()) == 0;
-    };
-
-    size_t delimiter_size(char) {
-        return 1;
-    }
-    size_t delimiter_size(const std::string& delim) {
-        return delim.size();
-    }
-
-    void trim_if_enabled(char*& curr) {
-        if constexpr (trim::enabled) {
-            while (trim::match(*curr)) {
-                ++curr;
-            }
-        }
-    }
-
-    void shift_if_escaped(char*& curr_i) {
-        if constexpr (escape::enabled) {
-            if (escape::match(*curr_i)) {
-                *curr = end[1];
-                ++end;
-            }
-        }
-    }
-
-    void shift() {
-        *curr = *end;
-        ++end;
-        ++curr;
-    }
-
-    void shift(size_t n) {
-        memcpy(curr, end, n);
-        end += n;
-        curr += n;
-    }
-
-    template <typename Delim>
-    std::tuple<size_t, bool> match_delimiter(char* begin, const Delim& delim) {
-        char* end_i = begin;
-
-        trim_if_enabled(end_i);
-
-        // just spacing
-        if (*end_i == '\0') {
-            return {0, false};
-        }
-
-        // not a delimiter
-        if (!match(end_i, delim)) {
-            shift_if_escaped(end_i);
-            return {1 + end_i - begin, false};
-        }
-
-        end_i += delimiter_size(delim);
-        trim_if_enabled(end_i);
-
-        // delimiter
-        return {end_i - begin, true};
-    }
-
-public:
-    bool valid() {
-        return error_.empty();
-    }
-
-    split_input& split(char* new_line, const std::string& d = ",") {
-        line = new_line;
-        output_.clear();
-        switch (d.size()) {
-        case 0:
-            // set error
-            return output_;
-        case 1:
-            return split_impl(d[0]);
-        default:
-            return split_impl(d);
-        }
-    }
-
-    template <typename Delim>
-    std::vector<range>& split_impl(const Delim& delim) {
-        state = State::begin;
-        begin = line;
-
-        trim_if_enabled(begin);
-
-        while (state != State::finished) {
-            curr = end = begin;
-            switch (state) {
-            case (State::begin):
-                state_begin();
-                break;
-            case (State::reading):
-                state_reading(delim);
-                break;
-            case (State::quoting):
-                state_quoting(delim);
-                break;
-            default:
-                break;
-            };
-        }
-
-        return output_;
-    }
-
-    void state_begin() {
-        if constexpr (quote::enabled) {
-            if (quote::match(*begin)) {
-                ++begin;
-                state = State::quoting;
-                return;
-            }
-        }
-        state = State::reading;
-    }
-
-    template <typename Delim>
-    void state_reading(const Delim& delim) {
-        while (true) {
-            auto [width, valid] = match_delimiter(end, delim);
-
-            // not a delimiter
-            if (!valid) {
-                if (width == 0) {
-                    // eol
-                    output_.emplace_back(begin, curr);
-                    state = State::finished;
-                    break;
-                } else {
-                    shift(width);
-                    continue;
-                }
-            }
-
-            // found delimiter
-            push_and_start_next(width);
-            break;
-        }
-    }
-
-    template <typename Delim>
-    void state_quoting(const Delim& delim) {
-        if constexpr (quote::enabled) {
-            while (true) {
-                if (quote::match(*end)) {
-                    // double quote
-                    // eg: ...,"hel""lo,... -> hel"lo
-                    if (quote::match(end[1])) {
-                        ++end;
-                        shift();
-                        continue;
-                    }
-
-                    auto [width, valid] = match_delimiter(end + 1, delim);
-
-                    // not a delimiter
-                    if (!valid) {
-                        if (width == 0) {
-                            // eol
-                            // eg: ...,"hello"   \0 -> hello
-                            // eg no trim: ...,"hello"\0 -> hello
-                            output_.emplace_back(begin, curr);
-                        } else {
-                            // missmatched quote
-                            // eg: ...,"hel"lo,... -> error
-                        }
-                        state = State::finished;
-                        break;
-                    }
-
-                    // delimiter
-                    push_and_start_next(width + 1);
-                    break;
-                }
-
-                if constexpr (escape::enabled) {
-                    if (escape::match(*end)) {
-                        ++end;
-                        shift();
-                        continue;
-                    }
-                }
-
-                // unterminated error
-                // eg: ..."hell\0 -> quote not terminated
-                if (*end == '\0') {
-                    *curr = '\0';
-                    state = State::finished;
-                    break;
-                }
-                shift();
-            }
-        } else {
-            // set error impossible scenario
-            state = State::finished;
-        }
-    }
-
-    void push_and_start_next(size_t n) {
-        output_.emplace_back(begin, curr);
-        begin = end + n;
-        state = State::begin;
-    }
-
-private:
-    std::vector<range> output_;
-    std::string error_ = "";
-    State state;
-    char* curr;
-    char* end;
-    char* begin;
-    char* line;
-};
-
-////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////
-
 ////////////////
 // converter
 ////////////////
diff --git a/include/ss/splitter.hpp b/include/ss/splitter.hpp
new file mode 100644
index 0000000..70867f7
--- /dev/null
+++ b/include/ss/splitter.hpp
@@ -0,0 +1,345 @@
+#pragma once
+#include "type_traits.hpp"
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <vector>
+
+namespace ss {
+template <char... Cs>
+struct matcher {
+private:
+    template <char X, char... Xs>
+    static bool match_impl(char c) {
+        if constexpr (sizeof...(Xs) != 0) {
+            return (c == X) || match_impl<Xs...>(c);
+        }
+        return (c == X);
+    }
+
+public:
+    static bool match(char c) {
+        return match_impl<Cs...>(c);
+    }
+    constexpr static bool enabled = true;
+};
+
+template <>
+class matcher<'\0'> {
+public:
+    constexpr static bool enabled = false;
+    static bool match(char c) = delete;
+};
+
+////////////////
+// is instance of
+////////////////
+
+template <typename T, template <char...> class Template>
+struct is_instance_of_char {
+    constexpr static bool value = false;
+};
+
+template <char... Ts, template <char...> class Template>
+struct is_instance_of_char<Template<Ts...>, Template> {
+    constexpr static bool value = true;
+};
+
+///////////////////////////////////////////////////
+
+template <char... Cs>
+struct quote : matcher<Cs...> {};
+
+template <char... Cs>
+struct trim : matcher<Cs...> {};
+
+template <char... Cs>
+struct escape : matcher<Cs...> {};
+
+/////////////////////////////////////////////////
+// -> type traits
+template <bool B, typename T, typename U>
+struct if_then_else;
+
+template <typename T, typename U>
+struct if_then_else<true, T, U> {
+    using type = T;
+};
+
+template <typename T, typename U>
+struct if_then_else<false, T, U> {
+    using type = U;
+};
+
+//////////////////////////////////////////////
+template <template <char...> class Matcher, typename... Ts>
+struct get_matcher;
+
+template <template <char...> class Matcher, typename T, typename... Ts>
+struct get_matcher<Matcher, T, Ts...> {
+    using type =
+        typename if_then_else<is_instance_of_char<T, Matcher>::value, T,
+                              typename get_matcher<Matcher, Ts...>::type>::type;
+};
+
+template <template <char...> class Matcher>
+struct get_matcher<Matcher> {
+    using type = Matcher<'\0'>;
+};
+
+///////////////////////////////////////////////
+// TODO add restriction
+template <typename... Ts>
+struct setup {
+    using quote = typename get_matcher<quote, Ts...>::type;
+    using trim = typename get_matcher<trim, Ts...>::type;
+    using escape = typename get_matcher<escape, Ts...>::type;
+};
+
+template <typename... Ts>
+struct setup<setup<Ts...>> : setup<Ts...> {};
+
+/////////////////////////////////////////////////////////////////////////////
+
+enum class State { finished, begin, reading, quoting };
+using range = std::pair<const char*, const char*>;
+
+using string_range = std::pair<const char*, const char*>;
+using split_input = std::vector<string_range>;
+
+template <typename... Ts>
+class splitter {
+    using Setup = setup<Ts...>;
+    using quote = typename Setup::quote;
+    using trim = typename Setup::trim;
+    using escape = typename Setup::escape;
+
+    bool match(const char* end_i, char delim) {
+        return *end_i == delim;
+    };
+
+    bool match(const char* end_i, const std::string& delim) {
+        return strncmp(end_i, delim.c_str(), delim.size()) == 0;
+    };
+
+    size_t delimiter_size(char) {
+        return 1;
+    }
+
+    size_t delimiter_size(const std::string& delim) {
+        return delim.size();
+    }
+
+    void trim_if_enabled(char*& curr) {
+        if constexpr (trim::enabled) {
+            while (trim::match(*curr)) {
+                ++curr;
+            }
+        }
+    }
+
+    void shift_if_escaped(char*& curr_i) {
+        if constexpr (escape::enabled) {
+            if (escape::match(*curr_i)) {
+                *curr = end[1];
+                ++end;
+            }
+        }
+    }
+
+    void shift() {
+        if constexpr (escape::enabled || quote::enabled) {
+            *curr = *end;
+        }
+        ++end;
+        ++curr;
+    }
+
+    void shift(size_t n) {
+        if constexpr (escape::enabled || quote::enabled) {
+            memcpy(curr, end, n);
+        }
+        end += n;
+        curr += n;
+    }
+
+    template <typename Delim>
+    std::tuple<size_t, bool> match_delimiter(char* begin, const Delim& delim) {
+        char* end_i = begin;
+
+        trim_if_enabled(end_i);
+
+        // just spacing
+        if (*end_i == '\0') {
+            return {0, false};
+        }
+
+        // not a delimiter
+        if (!match(end_i, delim)) {
+            shift_if_escaped(end_i);
+            return {1 + end_i - begin, false};
+        }
+
+        end_i += delimiter_size(delim);
+        trim_if_enabled(end_i);
+
+        // delimiter
+        return {end_i - begin, true};
+    }
+
+public:
+    bool valid() {
+        return error_.empty();
+    }
+
+    split_input& split(char* new_line, const std::string& d = ",") {
+        line = new_line;
+        output_.clear();
+        switch (d.size()) {
+        case 0:
+            // set error
+            return output_;
+        case 1:
+            return split_impl(d[0]);
+        default:
+            return split_impl(d);
+        }
+    }
+
+    template <typename Delim>
+    std::vector<range>& split_impl(const Delim& delim) {
+        state = State::begin;
+        begin = line;
+
+        trim_if_enabled(begin);
+
+        while (state != State::finished) {
+            curr = end = begin;
+            switch (state) {
+            case (State::begin):
+                state_begin();
+                break;
+            case (State::reading):
+                state_reading(delim);
+                break;
+            case (State::quoting):
+                state_quoting(delim);
+                break;
+            default:
+                break;
+            };
+        }
+
+        return output_;
+    }
+
+    void state_begin() {
+        if constexpr (quote::enabled) {
+            if (quote::match(*begin)) {
+                ++begin;
+                state = State::quoting;
+                return;
+            }
+        }
+        state = State::reading;
+    }
+
+    template <typename Delim>
+    void state_reading(const Delim& delim) {
+        while (true) {
+            auto [width, valid] = match_delimiter(end, delim);
+
+            // not a delimiter
+            if (!valid) {
+                if (width == 0) {
+                    // eol
+                    output_.emplace_back(begin, curr);
+                    state = State::finished;
+                    break;
+                } else {
+                    shift(width);
+                    continue;
+                }
+            }
+
+            // found delimiter
+            push_and_start_next(width);
+            break;
+        }
+    }
+
+    template <typename Delim>
+    void state_quoting(const Delim& delim) {
+        if constexpr (quote::enabled) {
+            while (true) {
+                if (quote::match(*end)) {
+                    // double quote
+                    // eg: ...,"hel""lo,... -> hel"lo
+                    if (quote::match(end[1])) {
+                        ++end;
+                        shift();
+                        continue;
+                    }
+
+                    auto [width, valid] = match_delimiter(end + 1, delim);
+
+                    // not a delimiter
+                    if (!valid) {
+                        if (width == 0) {
+                            // eol
+                            // eg: ...,"hello"   \0 -> hello
+                            // eg no trim: ...,"hello"\0 -> hello
+                            output_.emplace_back(begin, curr);
+                        } else {
+                            // missmatched quote
+                            // eg: ...,"hel"lo,... -> error
+                        }
+                        state = State::finished;
+                        break;
+                    }
+
+                    // delimiter
+                    push_and_start_next(width + 1);
+                    break;
+                }
+
+                if constexpr (escape::enabled) {
+                    if (escape::match(*end)) {
+                        ++end;
+                        shift();
+                        continue;
+                    }
+                }
+
+                // unterminated error
+                // eg: ..."hell\0 -> quote not terminated
+                if (*end == '\0') {
+                    *curr = '\0';
+                    state = State::finished;
+                    break;
+                }
+                shift();
+            }
+        } else {
+            // set error impossible scenario
+            state = State::finished;
+        }
+    }
+
+    void push_and_start_next(size_t n) {
+        output_.emplace_back(begin, curr);
+        begin = end + n;
+        state = State::begin;
+    }
+
+private:
+    std::vector<range> output_;
+    std::string error_ = "";
+    State state;
+    char* curr;
+    char* end;
+    char* begin;
+    char* line;
+};
+
+} /* ss */
diff --git a/test/makefile b/test/makefile
index 9bbe159..2b4f851 100644
--- a/test/makefile
+++ b/test/makefile
@@ -1,6 +1,6 @@
 CXX=clang++
 CXXFLAGS=-Wall -Wextra -std=c++17 -lstdc++fs
-TESTS=test_parser test_converter test_extractions
+TESTS=test_parser test_converter test_extractions test_splitter
 
 all: $(TESTS)
 
diff --git a/test/test_converter.cpp b/test/test_converter.cpp
index f9f7631..e708fef 100644
--- a/test/test_converter.cpp
+++ b/test/test_converter.cpp
@@ -16,105 +16,7 @@ public:
     }
 };
 
-buffer buff;
-
-TEST_CASE("testing splitter with escaping") {
-    std::vector<std::string> values{"10",   "he\\\"llo",
-                                    "\\\"", "\\\"a\\,a\\\"",
-                                    "3.33", "a\\\""};
-
-    char buff[128];
-    // with quote
-    ss::splitter<ss::quote<'"'>, ss::escape<'\\'>> s;
-    std::string delim = ",";
-    for (size_t i = 0; i < values.size() * values.size(); ++i) {
-        std::string input1;
-        std::string input2;
-        for (size_t j = 0; j < values.size(); ++j) {
-            if (i & (1 << j) && j != 2 && j != 3) {
-                input1.append(values[j]);
-                input2.append(values.at(values.size() - 1 - j));
-            } else {
-                input1.append("\"" + values[j] + "\"");
-                input2.append("\"" + values.at(values.size() - 1 - j) + "\"");
-            }
-            input1.append(delim);
-            input2.append(delim);
-        }
-        input1.pop_back();
-        input2.pop_back();
-        input1.append("\0\"");
-        input2.append("\0\"");
-
-        memcpy(buff, input1.c_str(), input1.size() + 1);
-        auto tup1 = s.split(buff, delim);
-        CHECK(tup1.size() == 6);
-
-        memcpy(buff, input2.c_str(), input2.size() + 1);
-        auto tup2 = s.split(buff, delim);
-        CHECK(tup2.size() == 6);
-    }
-}
-
-/*
-TEST_CASE("testing quoting without escaping") {
-    std::vector<std::string> values{"10", "hello", ",", "a,a", "3.33", "a"};
-
-    // with quote
-    ss::converter c;
-    for (size_t i = 0; i < values.size() * values.size(); ++i) {
-        std::string input1;
-        std::string input2;
-        for (size_t j = 0; j < values.size(); ++j) {
-            if (i & (1 << j) && j != 2 && j != 3) {
-                input1.append(values[j]);
-                input2.append(values.at(values.size() - 1 - j));
-            } else {
-                input1.append("\"" + values[j] + "\"");
-                input2.append("\"" + values.at(values.size() - 1 - j) + "\"");
-            }
-            input1.append("__");
-            input1.push_back(',');
-            input1.append("__");
-            input2.push_back(',');
-        }
-        input1.pop_back();
-        input1.pop_back();
-        input1.pop_back();
-        input2.pop_back();
-        input1.append("\0\"");
-        input2.append("\0\"");
-
-        auto tup1 = c.convert<int, std::string, std::string, std::string,
-                              double, char>(input1.c_str(), ",");
-        if (!c.valid()) {
-            FAIL("invalid: " + input1);
-        } else {
-            auto [a, b, c, d, e, f] = tup1;
-            CHECK(a == 10);
-            CHECK(b == "hello");
-            CHECK(c == ",");
-            CHECK(d == "a,a");
-            CHECK(e == 3.33);
-            CHECK(f == 'a');
-        }
-
-        auto tup2 = c.convert<char, double, std::string, std::string,
-                              std::string, int>(input2.c_str(), ",");
-        if (!c.valid()) {
-            FAIL("invalid: " + input2);
-        } else {
-            auto [f, e, d, c, b, a] = tup2;
-            CHECK(a == 10);
-            CHECK(b == "hello");
-            CHECK(c == ",");
-            CHECK(d == "a,a");
-            CHECK(e == 3.33);
-            CHECK(f == 'a');
-        }
-    }
-}
-*/
+static buffer buff;
 
 TEST_CASE("testing split") {
     ss::converter c;
diff --git a/test/test_splitter.cpp b/test/test_splitter.cpp
new file mode 100644
index 0000000..22c37a2
--- /dev/null
+++ b/test/test_splitter.cpp
@@ -0,0 +1,43 @@
+#include <iostream>
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "../include/ss/splitter.hpp"
+#include "doctest.h"
+#include <algorithm>
+
+TEST_CASE("testing splitter with escaping") {
+    std::vector<std::string> values{"10",   "he\\\"llo",
+                                    "\\\"", "\\\"a\\,a\\\"",
+                                    "3.33", "a\\\""};
+
+    char buff[128];
+    // with quote
+    ss::splitter<ss::quote<'"'>, ss::escape<'\\'>> s;
+    std::string delim = ",";
+    for (size_t i = 0; i < values.size() * values.size(); ++i) {
+        std::string input1;
+        std::string input2;
+        for (size_t j = 0; j < values.size(); ++j) {
+            if (i & (1 << j) && j != 2 && j != 3) {
+                input1.append(values[j]);
+                input2.append(values.at(values.size() - 1 - j));
+            } else {
+                input1.append("\"" + values[j] + "\"");
+                input2.append("\"" + values.at(values.size() - 1 - j) + "\"");
+            }
+            input1.append(delim);
+            input2.append(delim);
+        }
+        input1.pop_back();
+        input2.pop_back();
+        input1.append("\0\"");
+        input2.append("\0\"");
+
+        memcpy(buff, input1.c_str(), input1.size() + 1);
+        auto tup1 = s.split(buff, delim);
+        CHECK(tup1.size() == 6);
+
+        memcpy(buff, input2.c_str(), input2.size() + 1);
+        auto tup2 = s.split(buff, delim);
+        CHECK(tup2.size() == 6);
+    }
+}