Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: 93712b24bf
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibRegex/RegexLexer.h

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2020, Emanuel Sprung <emanuel.sprung@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Forward.h>
+#include <AK/GenericLexer.h>
+#include <AK/StringView.h>
+
+namespace regex {
+
+#define ENUMERATE_REGEX_TOKENS              \
+    __ENUMERATE_REGEX_TOKEN(Eof)            \
+    __ENUMERATE_REGEX_TOKEN(Char)           \
+    __ENUMERATE_REGEX_TOKEN(Circumflex)     \
+    __ENUMERATE_REGEX_TOKEN(Period)         \
+    __ENUMERATE_REGEX_TOKEN(LeftParen)      \
+    __ENUMERATE_REGEX_TOKEN(RightParen)     \
+    __ENUMERATE_REGEX_TOKEN(LeftCurly)      \
+    __ENUMERATE_REGEX_TOKEN(RightCurly)     \
+    __ENUMERATE_REGEX_TOKEN(LeftBracket)    \
+    __ENUMERATE_REGEX_TOKEN(RightBracket)   \
+    __ENUMERATE_REGEX_TOKEN(Asterisk)       \
+    __ENUMERATE_REGEX_TOKEN(EscapeSequence) \
+    __ENUMERATE_REGEX_TOKEN(Dollar)         \
+    __ENUMERATE_REGEX_TOKEN(Pipe)           \
+    __ENUMERATE_REGEX_TOKEN(Plus)           \
+    __ENUMERATE_REGEX_TOKEN(Comma)          \
+    __ENUMERATE_REGEX_TOKEN(Slash)          \
+    __ENUMERATE_REGEX_TOKEN(EqualSign)      \
+    __ENUMERATE_REGEX_TOKEN(HyphenMinus)    \
+    __ENUMERATE_REGEX_TOKEN(Colon)          \
+    __ENUMERATE_REGEX_TOKEN(Questionmark)
+
+enum class TokenType {
+#define __ENUMERATE_REGEX_TOKEN(x) x,
+    ENUMERATE_REGEX_TOKENS
+#undef __ENUMERATE_REGEX_TOKEN
+};
+
+class Token {
+public:
+    Token() = default;
+    Token(TokenType const type, size_t const start_position, StringView const value)
+        : m_type(type)
+        , m_position(start_position)
+        , m_value(value)
+    {
+    }
+
+    TokenType type() const { return m_type; }
+    StringView value() const { return m_value; }
+    size_t position() const { return m_position; }
+
+    char const* name() const;
+    static char const* name(TokenType);
+
+private:
+    TokenType m_type { TokenType::Eof };
+    size_t m_position { 0 };
+    StringView m_value {};
+};
+
+class Lexer : public GenericLexer {
+public:
+    Lexer();
+    explicit Lexer(StringView source);
+    Token next();
+    void reset();
+    void back(size_t offset);
+    char consume();
+    void set_source(StringView const source) { m_input = source; }
+    auto const& source() const { return m_input; }
+
+private:
+    size_t m_previous_position { 0 };
+    Token m_current_token { TokenType::Eof, 0, {} };
+};
+
+}
+
+using regex::Lexer;