basic json parsing added

null not supported correctly

.gitignore

@@ -1 +1,2 @@
 build
+/cmake-build-debug/

.vscode/c_cpp_properties.json

@@ -4,14 +4,14 @@
             "name": "Mac",
             "includePath": [
                 "${workspaceFolder}/**",
-                "${workspaceFolder}/stdlib"
+                "${workspaceFolder}/clib"
             ],
             "defines": [],
             "macFrameworkPath": [
                 "/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks"
             ],
             "compilerPath": "/usr/bin/clang",
-            "cStandard": "c11",
+            "cStandard": "c17",
             "intelliSenseMode": "macos-clang-x64",
             "configurationProvider": "ms-vscode.cmake-tools"
         }

CMakeLists.txt

@@ -21,7 +21,8 @@ set(PROJECT_NAME ml)
 set(SOURCE
 	ml.cpp
 	clib/csvparser.cpp
-	clib/sslclient.cpp)
+	clib/sslclient.cpp
+	clib/json11.cpp)
 
 add_executable(${PROJECT_NAME} ${SOURCE})
 

Readme.md

@@ -1,7 +1,9 @@
 
 ### TODO
+- support for strings with " included
 - update openssl libs
-
+- documentation
+- add url of source/inspiration to clib/*.cpp
 
 #### Functionality
 - readline
@@ -12,7 +14,8 @@
 - env
 - support for including lib
 - date support
-
+- file functions
+- string funtions
 
 
 #### Performance

clib/json11.cpp

@@ -0,0 +1,854 @@
+
+#include "json11.h"
+#include <cassert>
+#include <cmath>
+#include <cstdlib>
+#include <cstdio>
+#include <limits>
+
+namespace json11 {
+
+    static const int max_depth = 200;
+
+    using std::string;
+    using std::vector;
+    using std::map;
+    using std::make_shared;
+    using std::initializer_list;
+    using std::move;
+
+/* Helper for representing null - just a do-nothing struct, plus comparison
+ * operators so the helpers in JsonValue work. We can't use nullptr_t because
+ * it may not be orderable.
+ */
+    struct NullStruct {
+        bool operator==(NullStruct) const { return true; }
+        bool operator<(NullStruct) const { return false; }
+    };
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Serialization
+ */
+
+    static void dump(NullStruct, string &out) {
+        out += "null";
+    }
+
+    static void dump(double value, string &out) {
+        if (std::isfinite(value)) {
+            char buf[32];
+            snprintf(buf, sizeof buf, "%.17g", value);
+            out += buf;
+        } else {
+            out += "null";
+        }
+    }
+
+    static void dump(int value, string &out) {
+        char buf[32];
+        snprintf(buf, sizeof buf, "%d", value);
+        out += buf;
+    }
+
+    static void dump(bool value, string &out) {
+        out += value ? "true" : "false";
+    }
+
+    static void dump(const string &value, string &out) {
+        out += '"';
+        for (size_t i = 0; i < value.length(); i++) {
+            const char ch = value[i];
+            if (ch == '\\') {
+                out += "\\\\";
+            } else if (ch == '"') {
+                out += "\\\"";
+            } else if (ch == '\b') {
+                out += "\\b";
+            } else if (ch == '\f') {
+                out += "\\f";
+            } else if (ch == '\n') {
+                out += "\\n";
+            } else if (ch == '\r') {
+                out += "\\r";
+            } else if (ch == '\t') {
+                out += "\\t";
+            } else if (static_cast<uint8_t>(ch) <= 0x1f) {
+                char buf[8];
+                snprintf(buf, sizeof buf, "\\u%04x", ch);
+                out += buf;
+            } else if (static_cast<uint8_t>(ch) == 0xe2 && static_cast<uint8_t>(value[i+1]) == 0x80
+                       && static_cast<uint8_t>(value[i+2]) == 0xa8) {
+                out += "\\u2028";
+                i += 2;
+            } else if (static_cast<uint8_t>(ch) == 0xe2 && static_cast<uint8_t>(value[i+1]) == 0x80
+                       && static_cast<uint8_t>(value[i+2]) == 0xa9) {
+                out += "\\u2029";
+                i += 2;
+            } else {
+                out += ch;
+            }
+        }
+        out += '"';
+    }
+
+    static void dump(const Json::array &values, string &out) {
+        bool first = true;
+        out += "[";
+        for (const auto &value : values) {
+            if (!first)
+                out += ", ";
+            value.dump(out);
+            first = false;
+        }
+        out += "]";
+    }
+
+    static void dump(const Json::object &values, string &out) {
+        bool first = true;
+        out += "{";
+        for (const auto &kv : values) {
+            if (!first)
+                out += ", ";
+            dump(kv.first, out);
+            out += ": ";
+            kv.second.dump(out);
+            first = false;
+        }
+        out += "}";
+    }
+
+    void Json::dump(string &out) const {
+        m_ptr->dump(out);
+    }
+
+////////////////////////
+
+    static MlValue ivalualize(NullStruct) {
+        MlValue null;
+        return null;
+    }
+
+    static MlValue ivalualize(double value) {
+        MlValue d;
+        if (std::isfinite(value)) {
+            d = value;
+        }
+        return d;
+    }
+
+    static MlValue ivalualize(int value) {
+        return MlValue(value);
+    }
+
+    static MlValue ivalualize(bool value) {
+        return MlValue(value);
+    }
+
+    static MlValue ivalualize(const string& value) {
+        return MlValue::string(value);
+    }
+
+    static MlValue ivalualize(const Json::array &values) {
+        vector<MlValue> arry;
+        for (const auto &value : values) {
+            arry.push_back(value.ivalualize());
+        }
+        return arry;
+    }
+
+    static MlValue ivalualize(const Json::object &values) {
+        vector<MlValue> map;
+
+        for (const auto &kv : values) {
+            std::string first = kv.first;
+            Json second = kv.second;
+
+            vector<MlValue> pair;
+            pair.push_back(MlValue::string(first));
+            pair.push_back(second.ivalualize());
+
+            map.push_back(pair);
+        }
+        return map;
+    }
+
+    MlValue Json::ivalualize() const {
+        return m_ptr->ivalualize();
+    }
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Value wrappers
+ */
+
+    template <Json::Type tag, typename T>
+    class Value : public JsonValue {
+    protected:
+
+        // Constructors
+        explicit Value(const T &value) : m_value(value) {}
+        explicit Value(T &&value)      : m_value(move(value)) {}
+
+        // Get type tag
+        Json::Type type() const override {
+            return tag;
+        }
+
+        // Comparisons
+        bool equals(const JsonValue * other) const override {
+            return m_value == static_cast<const Value<tag, T> *>(other)->m_value;
+        }
+        bool less(const JsonValue * other) const override {
+            return m_value < static_cast<const Value<tag, T> *>(other)->m_value;
+        }
+
+        const T m_value;
+        void dump(string &out) const override { json11::dump(m_value, out); }
+
+        MlValue ivalualize() const override { return json11::ivalualize(m_value); }
+    };
+
+    class JsonDouble final : public Value<Json::NUMBER, double> {
+        double number_value() const override { return m_value; }
+        int int_value() const override { return static_cast<int>(m_value); }
+        bool equals(const JsonValue * other) const override { return m_value == other->number_value(); }
+        bool less(const JsonValue * other)   const override { return m_value <  other->number_value(); }
+    public:
+        explicit JsonDouble(double value) : Value(value) {}
+    };
+
+    class JsonInt final : public Value<Json::NUMBER, int> {
+        double number_value() const override { return m_value; }
+        int int_value() const override { return m_value; }
+        bool equals(const JsonValue * other) const override { return m_value == other->number_value(); }
+        bool less(const JsonValue * other)   const override { return m_value <  other->number_value(); }
+    public:
+        explicit JsonInt(int value) : Value(value) {}
+    };
+
+    class JsonBoolean final : public Value<Json::BOOL, bool> {
+        bool bool_value() const override { return m_value; }
+    public:
+        explicit JsonBoolean(bool value) : Value(value) {}
+    };
+
+    class JsonString final : public Value<Json::STRING, string> {
+        const string &string_value() const override { return m_value; }
+    public:
+        explicit JsonString(const string &value) : Value(value) {}
+        explicit JsonString(string &&value)      : Value(move(value)) {}
+    };
+
+    class JsonArray final : public Value<Json::ARRAY, Json::array> {
+        const Json::array &array_items() const override { return m_value; }
+        const Json & operator[](size_t i) const override;
+    public:
+        explicit JsonArray(const Json::array &value) : Value(value) {}
+        explicit JsonArray(Json::array &&value)      : Value(move(value)) {}
+    };
+
+    class JsonObject final : public Value<Json::OBJECT, Json::object> {
+        const Json::object &object_items() const override { return m_value; }
+        const Json & operator[](const string &key) const override;
+    public:
+        explicit JsonObject(const Json::object &value) : Value(value) {}
+        explicit JsonObject(Json::object &&value)      : Value(move(value)) {}
+    };
+
+    class JsonNull final : public Value<Json::NUL, NullStruct> {
+    public:
+        JsonNull() : Value({}) {}
+    };
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Static globals - static-init-safe
+ */
+    struct Statics {
+        const std::shared_ptr<JsonValue> null = make_shared<JsonNull>();
+        const std::shared_ptr<JsonValue> t = make_shared<JsonBoolean>(true);
+        const std::shared_ptr<JsonValue> f = make_shared<JsonBoolean>(false);
+        const string empty_string;
+        const vector<Json> empty_vector;
+        const map<string, Json> empty_map;
+        Statics() {}
+    };
+
+    static const Statics & statics() {
+        static const Statics s {};
+        return s;
+    }
+
+    static const Json & static_null() {
+        // This has to be separate, not in Statics, because Json() accesses statics().null.
+        static const Json json_null;
+        return json_null;
+    }
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Constructors
+ */
+
+    Json::Json() noexcept                  : m_ptr(statics().null) {}
+    Json::Json(std::nullptr_t) noexcept    : m_ptr(statics().null) {}
+    Json::Json(double value)               : m_ptr(make_shared<JsonDouble>(value)) {}
+    Json::Json(int value)                  : m_ptr(make_shared<JsonInt>(value)) {}
+    Json::Json(bool value)                 : m_ptr(value ? statics().t : statics().f) {}
+    Json::Json(const string &value)        : m_ptr(make_shared<JsonString>(value)) {}
+    Json::Json(string &&value)             : m_ptr(make_shared<JsonString>(move(value))) {}
+    Json::Json(const char * value)         : m_ptr(make_shared<JsonString>(value)) {}
+    Json::Json(const Json::array &values)  : m_ptr(make_shared<JsonArray>(values)) {}
+    Json::Json(Json::array &&values)       : m_ptr(make_shared<JsonArray>(move(values))) {}
+    Json::Json(const Json::object &values) : m_ptr(make_shared<JsonObject>(values)) {}
+    Json::Json(Json::object &&values)      : m_ptr(make_shared<JsonObject>(move(values))) {}
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Accessors
+ */
+
+    Json::Type Json::type()                           const { return m_ptr->type();         }
+    double Json::number_value()                       const { return m_ptr->number_value(); }
+    int Json::int_value()                             const { return m_ptr->int_value();    }
+    bool Json::bool_value()                           const { return m_ptr->bool_value();   }
+    const string & Json::string_value()               const { return m_ptr->string_value(); }
+    const vector<Json> & Json::array_items()          const { return m_ptr->array_items();  }
+    const map<string, Json> & Json::object_items()    const { return m_ptr->object_items(); }
+    const Json & Json::operator[] (size_t i)          const { return (*m_ptr)[i];           }
+    const Json & Json::operator[] (const string &key) const { return (*m_ptr)[key];         }
+
+    double                    JsonValue::number_value()              const { return 0; }
+    int                       JsonValue::int_value()                 const { return 0; }
+    bool                      JsonValue::bool_value()                const { return false; }
+    const string &            JsonValue::string_value()              const { return statics().empty_string; }
+    const vector<Json> &      JsonValue::array_items()               const { return statics().empty_vector; }
+    const map<string, Json> & JsonValue::object_items()              const { return statics().empty_map; }
+    const Json &              JsonValue::operator[] (size_t)         const { return static_null(); }
+    const Json &              JsonValue::operator[] (const string &) const { return static_null(); }
+
+    const Json & JsonObject::operator[] (const string &key) const {
+        auto iter = m_value.find(key);
+        return (iter == m_value.end()) ? static_null() : iter->second;
+    }
+    const Json & JsonArray::operator[] (size_t i) const {
+        if (i >= m_value.size()) return static_null();
+        else return m_value[i];
+    }
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Comparison
+ */
+
+    bool Json::operator== (const Json &other) const {
+        if (m_ptr == other.m_ptr)
+            return true;
+        if (m_ptr->type() != other.m_ptr->type())
+            return false;
+
+        return m_ptr->equals(other.m_ptr.get());
+    }
+
+    bool Json::operator< (const Json &other) const {
+        if (m_ptr == other.m_ptr)
+            return false;
+        if (m_ptr->type() != other.m_ptr->type())
+            return m_ptr->type() < other.m_ptr->type();
+
+        return m_ptr->less(other.m_ptr.get());
+    }
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Parsing
+ */
+
+/* esc(c)
+ *
+ * Format char c suitable for printing in an error message.
+ */
+    static inline string esc(char c) {
+        char buf[12];
+        if (static_cast<uint8_t>(c) >= 0x20 && static_cast<uint8_t>(c) <= 0x7f) {
+            snprintf(buf, sizeof buf, "'%c' (%d)", c, c);
+        } else {
+            snprintf(buf, sizeof buf, "(%d)", c);
+        }
+        return string(buf);
+    }
+
+    static inline bool in_range(long x, long lower, long upper) {
+        return (x >= lower && x <= upper);
+    }
+
+    namespace {
+/* JsonParser
+ *
+ * Object that tracks all state of an in-progress parse.
+ */
+        struct JsonParser final {
+
+            /* State
+             */
+            const string &str;
+            size_t i;
+            string &err;
+            bool failed;
+            const JsonParse strategy;
+
+            /* fail(msg, err_ret = Json())
+             *
+             * Mark this parse as failed.
+             */
+            Json fail(string &&msg) {
+                return fail(move(msg), Json());
+            }
+
+            template <typename T>
+            T fail(string &&msg, const T err_ret) {
+                if (!failed)
+                    err = std::move(msg);
+                failed = true;
+                return err_ret;
+            }
+
+            /* consume_whitespace()
+             *
+             * Advance until the current character is non-whitespace.
+             */
+            void consume_whitespace() {
+                while (str[i] == ' ' || str[i] == '\r' || str[i] == '\n' || str[i] == '\t')
+                    i++;
+            }
+
+            /* consume_comment()
+             *
+             * Advance comments (c-style inline and multiline).
+             */
+            bool consume_comment() {
+                bool comment_found = false;
+                if (str[i] == '/') {
+                    i++;
+                    if (i == str.size())
+                        return fail("unexpected end of input after start of comment", false);
+                    if (str[i] == '/') { // inline comment
+                        i++;
+                        // advance until next line, or end of input
+                        while (i < str.size() && str[i] != '\n') {
+                            i++;
+                        }
+                        comment_found = true;
+                    }
+                    else if (str[i] == '*') { // multiline comment
+                        i++;
+                        if (i > str.size()-2)
+                            return fail("unexpected end of input inside multi-line comment", false);
+                        // advance until closing tokens
+                        while (!(str[i] == '*' && str[i+1] == '/')) {
+                            i++;
+                            if (i > str.size()-2)
+                                return fail(
+                                        "unexpected end of input inside multi-line comment", false);
+                        }
+                        i += 2;
+                        comment_found = true;
+                    }
+                    else
+                        return fail("malformed comment", false);
+                }
+                return comment_found;
+            }
+
+            /* consume_garbage()
+             *
+             * Advance until the current character is non-whitespace and non-comment.
+             */
+            void consume_garbage() {
+                consume_whitespace();
+                if(strategy == JsonParse::COMMENTS) {
+                    bool comment_found = false;
+                    do {
+                        comment_found = consume_comment();
+                        if (failed) return;
+                        consume_whitespace();
+                    }
+                    while(comment_found);
+                }
+            }
+
+            /* get_next_token()
+             *
+             * Return the next non-whitespace character. If the end of the input is reached,
+             * flag an error and return 0.
+             */
+            char get_next_token() {
+                consume_garbage();
+                if (failed) return (char)0;
+                if (i == str.size())
+                    return fail("unexpected end of input", (char)0);
+
+                return str[i++];
+            }
+
+            /* encode_utf8(pt, out)
+             *
+             * Encode pt as UTF-8 and add it to out.
+             */
+            void encode_utf8(long pt, string & out) {
+                if (pt < 0)
+                    return;
+
+                if (pt < 0x80) {
+                    out += static_cast<char>(pt);
+                } else if (pt < 0x800) {
+                    out += static_cast<char>((pt >> 6) | 0xC0);
+                    out += static_cast<char>((pt & 0x3F) | 0x80);
+                } else if (pt < 0x10000) {
+                    out += static_cast<char>((pt >> 12) | 0xE0);
+                    out += static_cast<char>(((pt >> 6) & 0x3F) | 0x80);
+                    out += static_cast<char>((pt & 0x3F) | 0x80);
+                } else {
+                    out += static_cast<char>((pt >> 18) | 0xF0);
+                    out += static_cast<char>(((pt >> 12) & 0x3F) | 0x80);
+                    out += static_cast<char>(((pt >> 6) & 0x3F) | 0x80);
+                    out += static_cast<char>((pt & 0x3F) | 0x80);
+                }
+            }
+
+            /* parse_string()
+             *
+             * Parse a string, starting at the current position.
+             */
+            string parse_string() {
+                string out;
+                long last_escaped_codepoint = -1;
+                while (true) {
+                    if (i == str.size())
+                        return fail("unexpected end of input in string", "");
+
+                    char ch = str[i++];
+
+                    if (ch == '"') {
+                        encode_utf8(last_escaped_codepoint, out);
+                        return out;
+                    }
+
+                    if (in_range(ch, 0, 0x1f))
+                        return fail("unescaped " + esc(ch) + " in string", "");
+
+                    // The usual case: non-escaped characters
+                    if (ch != '\\') {
+                        encode_utf8(last_escaped_codepoint, out);
+                        last_escaped_codepoint = -1;
+                        out += ch;
+                        continue;
+                    }
+
+                    // Handle escapes
+                    if (i == str.size())
+                        return fail("unexpected end of input in string", "");
+
+                    ch = str[i++];
+
+                    if (ch == 'u') {
+                        // Extract 4-byte escape sequence
+                        string esc = str.substr(i, 4);
+                        // Explicitly check length of the substring. The following loop
+                        // relies on std::string returning the terminating NUL when
+                        // accessing str[length]. Checking here reduces brittleness.
+                        if (esc.length() < 4) {
+                            return fail("bad \\u escape: " + esc, "");
+                        }
+                        for (size_t j = 0; j < 4; j++) {
+                            if (!in_range(esc[j], 'a', 'f') && !in_range(esc[j], 'A', 'F')
+                                && !in_range(esc[j], '0', '9'))
+                                return fail("bad \\u escape: " + esc, "");
+                        }
+
+                        long codepoint = strtol(esc.data(), nullptr, 16);
+
+                        // JSON specifies that characters outside the BMP shall be encoded as a pair
+                        // of 4-hex-digit \u escapes encoding their surrogate pair components. Check
+                        // whether we're in the middle of such a beast: the previous codepoint was an
+                        // escaped lead (high) surrogate, and this is a trail (low) surrogate.
+                        if (in_range(last_escaped_codepoint, 0xD800, 0xDBFF)
+                            && in_range(codepoint, 0xDC00, 0xDFFF)) {
+                            // Reassemble the two surrogate pairs into one astral-plane character, per
+                            // the UTF-16 algorithm.
+                            encode_utf8((((last_escaped_codepoint - 0xD800) << 10)
+                                         | (codepoint - 0xDC00)) + 0x10000, out);
+                            last_escaped_codepoint = -1;
+                        } else {
+                            encode_utf8(last_escaped_codepoint, out);
+                            last_escaped_codepoint = codepoint;
+                        }
+
+                        i += 4;
+                        continue;
+                    }
+
+                    encode_utf8(last_escaped_codepoint, out);
+                    last_escaped_codepoint = -1;
+
+                    if (ch == 'b') {
+                        out += '\b';
+                    } else if (ch == 'f') {
+                        out += '\f';
+                    } else if (ch == 'n') {
+                        out += '\n';
+                    } else if (ch == 'r') {
+                        out += '\r';
+                    } else if (ch == 't') {
+                        out += '\t';
+                    } else if (ch == '"' || ch == '\\' || ch == '/') {
+                        out += ch;
+                    } else {
+                        return fail("invalid escape character " + esc(ch), "");
+                    }
+                }
+            }
+
+            /* parse_number()
+             *
+             * Parse a double.
+             */
+            Json parse_number() {
+                size_t start_pos = i;
+
+                if (str[i] == '-')
+                    i++;
+
+                // Integer part
+                if (str[i] == '0') {
+                    i++;
+                    if (in_range(str[i], '0', '9'))
+                        return fail("leading 0s not permitted in numbers");
+                } else if (in_range(str[i], '1', '9')) {
+                    i++;
+                    while (in_range(str[i], '0', '9'))
+                        i++;
+                } else {
+                    return fail("invalid " + esc(str[i]) + " in number");
+                }
+
+                if (str[i] != '.' && str[i] != 'e' && str[i] != 'E'
+                    && (i - start_pos) <= static_cast<size_t>(std::numeric_limits<int>::digits10)) {
+                    return std::atoi(str.c_str() + start_pos);
+                }
+
+                // Decimal part
+                if (str[i] == '.') {
+                    i++;
+                    if (!in_range(str[i], '0', '9'))
+                        return fail("at least one digit required in fractional part");
+
+                    while (in_range(str[i], '0', '9'))
+                        i++;
+                }
+
+                // Exponent part
+                if (str[i] == 'e' || str[i] == 'E') {
+                    i++;
+
+                    if (str[i] == '+' || str[i] == '-')
+                        i++;
+
+                    if (!in_range(str[i], '0', '9'))
+                        return fail("at least one digit required in exponent");
+
+                    while (in_range(str[i], '0', '9'))
+                        i++;
+                }
+
+                return std::strtod(str.c_str() + start_pos, nullptr);
+            }
+
+            /* expect(str, res)
+             *
+             * Expect that 'str' starts at the character that was just read. If it does, advance
+             * the input and return res. If not, flag an error.
+             */
+            Json expect(const string &expected, Json res) {
+                assert(i != 0);
+                i--;
+                if (str.compare(i, expected.length(), expected) == 0) {
+                    i += expected.length();
+                    return res;
+                } else {
+                    return fail("parse error: expected " + expected + ", got " + str.substr(i, expected.length()));
+                }
+            }
+
+            /* parse_json()
+             *
+             * Parse a JSON object.
+             */
+            Json parse_json(int depth) {
+                if (depth > max_depth) {
+                    return fail("exceeded maximum nesting depth");
+                }
+
+                char ch = get_next_token();
+                if (failed)
+                    return Json();
+
+                if (ch == '-' || (ch >= '0' && ch <= '9')) {
+                    i--;
+                    return parse_number();
+                }
+
+                if (ch == 't')
+                    return expect("true", true);
+
+                if (ch == 'f')
+                    return expect("false", false);
+
+                if (ch == 'n')
+                    return expect("null", Json());
+
+                if (ch == '"')
+                    return parse_string();
+
+                if (ch == '{') {
+                    map<string, Json> data;
+                    ch = get_next_token();
+                    if (ch == '}')
+                        return data;
+
+                    while (1) {
+                        if (ch != '"')
+                            return fail("expected '\"' in object, got " + esc(ch));
+
+                        string key = parse_string();
+                        if (failed)
+                            return Json();
+
+                        ch = get_next_token();
+                        if (ch != ':')
+                            return fail("expected ':' in object, got " + esc(ch));
+
+                        data[std::move(key)] = parse_json(depth + 1);
+                        if (failed)
+                            return Json();
+
+                        ch = get_next_token();
+                        if (ch == '}')
+                            break;
+                        if (ch != ',')
+                            return fail("expected ',' in object, got " + esc(ch));
+
+                        ch = get_next_token();
+                    }
+                    return data;
+                }
+
+                if (ch == '[') {
+                    vector<Json> data;
+                    ch = get_next_token();
+                    if (ch == ']')
+                        return data;
+
+                    while (1) {
+                        i--;
+                        data.push_back(parse_json(depth + 1));
+                        if (failed)
+                            return Json();
+
+                        ch = get_next_token();
+                        if (ch == ']')
+                            break;
+                        if (ch != ',')
+                            return fail("expected ',' in list, got " + esc(ch));
+
+                        ch = get_next_token();
+                        (void)ch;
+                    }
+                    return data;
+                }
+
+                return fail("expected value, got " + esc(ch));
+            }
+        };
+    }//namespace {
+
+    Json Json::parse(const string &in, string &err, JsonParse strategy) {
+        JsonParser parser { in, 0, err, false, strategy };
+        Json result = parser.parse_json(0);
+
+        // Check for any trailing garbage
+        parser.consume_garbage();
+        if (parser.failed)
+            return Json();
+        if (parser.i != in.size())
+            return parser.fail("unexpected trailing " + esc(in[parser.i]));
+
+        return result;
+    }
+
+// Documented in json11.hpp
+    vector<Json> Json::parse_multi(const string &in,
+                                   std::string::size_type &parser_stop_pos,
+                                   string &err,
+                                   JsonParse strategy) {
+        JsonParser parser { in, 0, err, false, strategy };
+        parser_stop_pos = 0;
+        vector<Json> json_vec;
+        while (parser.i != in.size() && !parser.failed) {
+            json_vec.push_back(parser.parse_json(0));
+            if (parser.failed)
+                break;
+
+            // Check for another object
+            parser.consume_garbage();
+            if (parser.failed)
+                break;
+            parser_stop_pos = parser.i;
+        }
+        return json_vec;
+    }
+
+/* * * * * * * * * * * * * * * * * * * *
+ * Shape-checking
+ */
+
+    bool Json::has_shape(const shape & types, string & err) const {
+        if (!is_object()) {
+            err = "expected JSON object, got " + dump();
+            return false;
+        }
+
+        for (auto & item : types) {
+            if ((*this)[item.first].type() != item.second) {
+                err = "bad type for " + item.first + " in " + dump();
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+} // namespace json11

clib/json11.h

@@ -0,0 +1,175 @@
+#pragma once
+
+#include "../ml.h"
+
+#include <string>
+#include <vector>
+#include <map>
+#include <memory>
+#include <initializer_list>
+
+namespace json11 {
+
+    enum JsonParse {
+        STANDARD, COMMENTS
+    };
+
+    class JsonValue;
+
+    class Json final {
+    public:
+        // Types
+        enum Type {
+            NUL, NUMBER, BOOL, STRING, ARRAY, OBJECT
+        };
+
+        // Array and object typedefs
+        typedef std::vector<Json> array;
+        typedef std::map<std::string, Json> object;
+
+        // Constructors for the various types of JSON value.
+        Json() noexcept;                // NUL
+        Json(std::nullptr_t) noexcept;  // NUL
+        Json(double value);             // NUMBER
+        Json(int value);                // NUMBER
+        Json(bool value);               // BOOL
+        Json(const std::string &value); // STRING
+        Json(std::string &&value);      // STRING
+        Json(const char * value);       // STRING
+        Json(const array &values);      // ARRAY
+        Json(array &&values);           // ARRAY
+        Json(const object &values);     // OBJECT
+        Json(object &&values);          // OBJECT
+
+        // Implicit constructor: anything with a to_json() function.
+        template <class T, class = decltype(&T::to_json)>
+        Json(const T & t) : Json(t.to_json()) {}
+
+        // Implicit constructor: map-like objects (std::map, std::unordered_map, etc)
+        template <class M, typename std::enable_if<
+                std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value
+                && std::is_constructible<Json, decltype(std::declval<M>().begin()->second)>::value,
+                int>::type = 0>
+        Json(const M & m) : Json(object(m.begin(), m.end())) {}
+
+        // Implicit constructor: vector-like objects (std::list, std::vector, std::set, etc)
+        template <class V, typename std::enable_if<
+                std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
+                int>::type = 0>
+        Json(const V & v) : Json(array(v.begin(), v.end())) {}
+
+        // This prevents Json(some_pointer) from accidentally producing a bool. Use
+        // Json(bool(some_pointer)) if that behavior is desired.
+        Json(void *) = delete;
+
+        // Accessors
+        Type type() const;
+
+        bool is_null()   const { return type() == NUL; }
+        bool is_number() const { return type() == NUMBER; }
+        bool is_bool()   const { return type() == BOOL; }
+        bool is_string() const { return type() == STRING; }
+        bool is_array()  const { return type() == ARRAY; }
+        bool is_object() const { return type() == OBJECT; }
+
+        // Return the enclosed value if this is a number, 0 otherwise. Note that json11 does not
+        // distinguish between integer and non-integer numbers - number_value() and int_value()
+        // can both be applied to a NUMBER-typed object.
+        double number_value() const;
+        int int_value() const;
+
+        // Return the enclosed value if this is a boolean, false otherwise.
+        bool bool_value() const;
+        // Return the enclosed string if this is a string, "" otherwise.
+        const std::string &string_value() const;
+        // Return the enclosed std::vector if this is an array, or an empty vector otherwise.
+        const array &array_items() const;
+        // Return the enclosed std::map if this is an object, or an empty map otherwise.
+        const object &object_items() const;
+
+        // Return a reference to arr[i] if this is an array, Json() otherwise.
+        const Json & operator[](size_t i) const;
+        // Return a reference to obj[key] if this is an object, Json() otherwise.
+        const Json & operator[](const std::string &key) const;
+
+        // Serialize.
+        void dump(std::string &out) const;
+        std::string dump() const {
+            std::string out;
+            dump(out);
+            return out;
+        }
+
+        MlValue ivalualize() const;
+
+        // Parse. If parse fails, return Json() and assign an error message to err.
+        static Json parse(const std::string & in,
+                          std::string & err,
+                          JsonParse strategy = JsonParse::STANDARD);
+        static Json parse(const char * in,
+                          std::string & err,
+                          JsonParse strategy = JsonParse::STANDARD) {
+            if (in) {
+                return parse(std::string(in), err, strategy);
+            } else {
+                err = "null input";
+                return nullptr;
+            }
+        }
+        // Parse multiple objects, concatenated or separated by whitespace
+        static std::vector<Json> parse_multi(
+                const std::string & in,
+                std::string::size_type & parser_stop_pos,
+                std::string & err,
+                JsonParse strategy = JsonParse::STANDARD);
+
+        static inline std::vector<Json> parse_multi(
+                const std::string & in,
+                std::string & err,
+                JsonParse strategy = JsonParse::STANDARD) {
+            std::string::size_type parser_stop_pos;
+            return parse_multi(in, parser_stop_pos, err, strategy);
+        }
+
+        bool operator== (const Json &rhs) const;
+        bool operator<  (const Json &rhs) const;
+        bool operator!= (const Json &rhs) const { return !(*this == rhs); }
+        bool operator<= (const Json &rhs) const { return !(rhs < *this); }
+        bool operator>  (const Json &rhs) const { return  (rhs < *this); }
+        bool operator>= (const Json &rhs) const { return !(*this < rhs); }
+
+        /* has_shape(types, err)
+         *
+         * Return true if this is a JSON object and, for each item in types, has a field of
+         * the given type. If not, return false and set err to a descriptive message.
+         */
+        typedef std::initializer_list<std::pair<std::string, Type>> shape;
+        bool has_shape(const shape & types, std::string & err) const;
+
+    private:
+        std::shared_ptr<JsonValue> m_ptr;
+    };
+
+// Internal class hierarchy - JsonValue objects are not exposed to users of this API.
+    class JsonValue {
+    protected:
+        friend class Json;
+        friend class JsonInt;
+        friend class JsonDouble;
+        virtual Json::Type type() const = 0;
+        virtual bool equals(const JsonValue * other) const = 0;
+        virtual bool less(const JsonValue * other) const = 0;
+        virtual void dump(std::string &out) const = 0;
+        virtual MlValue ivalualize() const = 0;
+        virtual double number_value() const;
+        virtual int int_value() const;
+        virtual bool bool_value() const;
+        virtual const std::string &string_value() const;
+        virtual const Json::array &array_items() const;
+        virtual const Json &operator[](size_t i) const;
+        virtual const Json::object &object_items() const;
+        virtual const Json &operator[](const std::string &key) const;
+        virtual ~JsonValue() {}
+    };
+
+} // namespace json11

clib/sslclient.cpp

@@ -172,7 +172,7 @@ int HttpClient::sslRequest(const std::string &server_name, const std::string &re
 	int s;
 	s = socket(AF_INET, SOCK_STREAM, 0);
 	if (!s) {
-		printf("Error creating socket.\n");
+		printf("MlError creating socket.\n");
 		return -1;
 	}
 
@@ -187,7 +187,7 @@ int HttpClient::sslRequest(const std::string &server_name, const std::string &re
 
 	// connect to server
 	if (connect(s, (struct sockaddr *)&sa, socklen)) {
-		printf("Error connecting to server.\n");
+		printf("MlError connecting to server.\n");
 		return -1;
 	}
 
@@ -198,7 +198,7 @@ int HttpClient::sslRequest(const std::string &server_name, const std::string &re
 	SSL_CTX *ctx = SSL_CTX_new(meth);
 	ssl = SSL_new(ctx);
 	if (!ssl) {
-		printf("Error creating SSL.\n");
+		printf("MlError creating SSL.\n");
 		log_ssl();
 		return -1;
 	}
@@ -209,7 +209,7 @@ int HttpClient::sslRequest(const std::string &server_name, const std::string &re
 
 	int err = SSL_connect(ssl);
 	if (err <= 0) {
-		printf("Error creating SSL connection.  err=%x\n", err);
+		printf("MlError creating SSL connection.  err=%x\n", err);
 		log_ssl();
 		fflush(stdout);
 		return -1;

debug.lisp

@@ -1,18 +1,24 @@
 (print "Debug starts")
 
-(include "tmp/example.lisp")
+(define json_list (read-json "{\"k1\":\"v1\", \"k2\":42, \"k3\":[\"a\",123,true,false,null]}"))
-(print "sorted: " (qs '(10 9 8 7 6 5 4 3 2 1)))
+(print json_list)
-
+(for x json_list
-(define csv (read-file "tmp/data.csv"))
-; (print csv)
-(define csv_list (parse-csv csv))
-; (print csv_list)
-(for x csv_list 
      (print x))
 
-(define web_page (read-url "https://query1.finance.yahoo.com/v7/finance/download/FDX?period1=1581272585&period2=1612894985&interval=1d&events=history&includeAdjustedClose=true"))
+
-(print web_page)
+;; (include "tmp/example.lisp")
-(define fdx_list (parse-csv (index web_page 1)))
+;; (print "sorted: " (qs '(10 9 8 7 6 5 4 3 2 1)))
-(print fdx_list)
+
+;; (define csv (read-file "tmp/data.csv"))
+;; ; (print csv)
+;; (define csv_list (parse-csv csv))
+;; ; (print csv_list)
+;; (for x csv_list 
+;;      (print x))
+
+;; (define web_page (read-url "https://query1.finance.yahoo.com/v7/finance/download/FDX?period1=1581272585&period2=1612894985&interval=1d&events=history&includeAdjustedClose=true"))
+;; (print web_page)
+;; (define fdx_list (parse-csv (index web_page 1)))
+;; (print fdx_list)
 
 (print "Debug ends")

ml.h

@@ -0,0 +1,210 @@
+#pragma once
+
+// Comment this define out to drop support for standard library functions.
+// This allows the program to run without a runtime.
+#define USE_STD
+
+
+#include <map>
+#include <string>
+#include <vector>
+#include <sstream>
+#include <exception>
+
+
+// // Forward declaration for MlEnvironment class definition
+class MlValue;
+
+
+// An instance of a function's scope.
+class MlEnvironment {
+public:
+    // Default constructor
+    MlEnvironment() : parent_scope(NULL) {}
+
+    // Does this environment, or its parent environment,
+    // have this atom in scope?
+    // This is only used to determine which atoms to capture when
+    // creating a lambda function.
+    bool has(std::string name) const;
+    // Get the value associated with this name in this scope
+    MlValue get(std::string name) const;
+    // Set the value associated with this name in this scope
+    void set(std::string name, MlValue value);
+
+    void combine(MlEnvironment const &other);
+
+    void set_parent_scope(MlEnvironment *parent) {
+        parent_scope = parent;
+    }
+
+    // Output this scope in readable form to a stream.
+    friend std::ostream &operator<<(std::ostream &os, MlEnvironment const &v);
+private:
+
+    // The definitions in the scope.
+    std::map<std::string, MlValue> defs;
+    MlEnvironment *parent_scope;
+};
+
+
+
+
+// An exception thrown by the lisp
+class MlError {
+public:
+    // Create an error with the value that caused the error,
+    // the scope where the error was found, and the message.
+    MlError(const MlValue &v, MlEnvironment const &env, const char *msg);
+    // Copy constructor is needed to prevent double frees
+    MlError(MlError const &other);
+    ~MlError();
+
+    // Get the printable error description.
+    std::string description();
+private:
+    MlValue *cause;
+    MlEnvironment env;
+    const char *msg;
+};
+
+
+
+// The type for a builtin function, which takes a list of values,
+// and the environment to run the function in.
+typedef MlValue (*Builtin)(std::vector<MlValue>, MlEnvironment &);
+
+
+ class MlValue {
+ public:
+
+     // Constructs a unit value
+     MlValue();
+
+     // Constructs an integer
+     MlValue(int i);
+     // Constructs a floating point value
+     MlValue(double f);
+     // Constructs a list
+     MlValue(const std::vector<MlValue> &list);
+
+     // Construct a quoted value
+     static MlValue quote(MlValue quoted);
+
+     // Construct an atom
+     static MlValue atom(const std::string &s);
+
+     // Construct a string
+     static MlValue string(const std::string &s);
+
+     // Construct a lambda function
+     MlValue(const std::vector<MlValue> &params, MlValue ret, MlEnvironment const &env);
+
+     // Construct a builtin function
+     MlValue(const std::string &name, Builtin b);
+
+     std::vector<std::string> get_used_atoms();
+
+     // Is this a builtin function?
+     bool is_builtin();
+
+     // Apply this as a function to a list of arguments in a given environment.
+     MlValue apply(std::vector<MlValue> args, MlEnvironment &env);
+     // Evaluate this value as lisp code.
+     MlValue eval(MlEnvironment &env);
+
+     bool is_number() const;
+
+     // Get the "truthy" boolean value of this value.
+     bool as_bool() const;
+
+     // Get this item's integer value
+     int as_int() const;
+
+     // Get this item's floating point value
+     double as_float() const;
+
+     // Get this item's string value
+     std::string as_string() const;
+
+     // Get this item's atom value
+     std::string as_atom() const;
+
+     // Get this item's list value
+     std::vector<MlValue> as_list() const;
+
+     // Push an item to the end of this list
+     void push(MlValue val);
+
+     // Push an item from the end of this list
+     MlValue pop();
+
+
+     // Cast this to an integer value
+     MlValue cast_to_int() const;
+
+     // Cast this to a floating point value
+     MlValue cast_to_float() const;
+
+
+     bool operator==(MlValue other) const;
+
+     bool operator!=(const MlValue &other) const;
+
+
+     bool operator>=(const MlValue &other) const;
+
+     bool operator<=(const MlValue &other) const;
+
+     bool operator>(const MlValue &other) const;
+
+     bool operator<(const MlValue &other) const;
+
+
+     // This function adds two lisp values, and returns the lisp value result.
+     MlValue operator+(const MlValue &other) const;
+
+     // This function subtracts two lisp values, and returns the lisp value result.
+     MlValue operator-(const MlValue &other) const;
+
+     // This function multiplies two lisp values, and returns the lisp value result.
+     MlValue operator*(const MlValue &other) const;
+
+     // This function divides two lisp values, and returns the lisp value result.
+     MlValue operator/(const MlValue &other) const;
+
+     // This function finds the remainder of two lisp values, and returns the lisp value result.
+     MlValue operator%(const MlValue &other) const;
+
+     // Get the name of the type of this value
+     std::string get_type_name();
+
+     std::string display() const;
+
+     std::string debug() const;
+
+     friend std::ostream &operator<<(std::ostream &os, MlValue const &v);
+
+ private:
+     enum {
+         QUOTE,
+         ATOM,
+         INT,
+         FLOAT,
+         LIST,
+         STRING,
+         LAMBDA,
+         BUILTIN,
+         UNIT
+     } type;
+
+     union {
+         int i;
+         double f;
+         Builtin b;
+     } stack_data;
+
+     std::string str;
+     std::vector<MlValue> list;
+     MlEnvironment lambda_scope;
+ };