ladybird/AK/GenericLexer.h
2020-09-26 17:17:53 +02:00

124 lines
3.7 KiB
C++

/*
* Copyright (c) 2020, Benoit Lormeau <blormeau@outlook.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Function.h>
#include <AK/StringView.h>
namespace AK {
class GenericLexer {
public:
explicit GenericLexer(const StringView& input);
virtual ~GenericLexer();
// A lambda/function can be used to match characters as the user pleases
using Condition = Function<bool(char)>;
size_t tell() const { return m_index; }
size_t tell_remaining() const { return m_input.length() - m_index; }
StringView remaining() const { return m_input.substring_view(m_index); }
bool is_eof() const;
char peek(size_t offset = 0) const;
bool next_is(char) const;
bool next_is(StringView) const;
bool next_is(const char*) const;
bool next_is(Condition) const;
char consume();
bool consume_specific(char);
bool consume_specific(StringView);
bool consume_specific(const char*);
StringView consume(size_t count);
StringView consume_all();
StringView consume_line();
StringView consume_while(Condition);
StringView consume_until(char);
StringView consume_until(const char*);
StringView consume_until(Condition);
// FIXME: provide an escape character
StringView consume_quoted_string();
void ignore(size_t count = 1);
void ignore_while(Condition);
void ignore_until(char);
void ignore_until(const char*);
void ignore_until(Condition);
protected:
StringView m_input;
size_t m_index { 0 };
};
constexpr auto is_any_of(const StringView& values)
{
return [values](auto c) { return values.contains(c); };
}
/*
* CType adapters: pass them as Conditions to a GenericLexer's methods
* Examples:
* - `if (lexer.next_is(is_digit))`
* - `auto name = lexer.consume_while(is_alphanum);
* - `lexer.ignore_until(is_any_of("<^>"))`
*/
bool is_alpha(char);
bool is_alphanum(char);
bool is_control(char);
bool is_digit(char);
bool is_graphic(char);
bool is_hex_digit(char);
bool is_lowercase(char);
bool is_path_separator(char);
bool is_printable(char);
bool is_punctuation(char);
bool is_quote(char);
bool is_uppercase(char);
bool is_whitespace(char);
}
using AK::GenericLexer;
using AK::is_alpha;
using AK::is_alphanum;
using AK::is_any_of;
using AK::is_control;
using AK::is_digit;
using AK::is_graphic;
using AK::is_hex_digit;
using AK::is_lowercase;
using AK::is_path_separator;
using AK::is_printable;
using AK::is_punctuation;
using AK::is_quote;
using AK::is_uppercase;
using AK::is_whitespace;