serenity/AK/SourceGenerator.h
asynts 61e73b1a7b AK: Introduce SourceGenerator::fork().
Previously, I abused the copy constructor, this is a lot better.
2020-10-24 12:56:25 +02:00

99 lines
3.6 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
* 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/GenericLexer.h>
#include <AK/HashMap.h>
#include <AK/String.h>
#include <AK/StringBuilder.h>
namespace AK {
class SourceGenerator {
AK_MAKE_NONCOPYABLE(SourceGenerator);
public:
using MappingType = HashMap<StringView, String>;
explicit SourceGenerator(StringBuilder& builder, char opening = '@', char closing = '@')
: m_builder(builder)
, m_opening(opening)
, m_closing(closing)
{
}
explicit SourceGenerator(StringBuilder& builder, const MappingType& mapping, char opening = '@', char closing = '@')
: m_builder(builder)
, m_mapping(mapping)
, m_opening(opening)
, m_closing(closing)
{
}
SourceGenerator fork() { return SourceGenerator { m_builder, m_mapping, m_opening, m_closing }; }
void set(StringView key, String value) { m_mapping.set(key, value); }
String get(StringView key) const { return m_mapping.get(key).value(); }
StringView as_string_view() const { return m_builder.string_view(); }
String as_string() const { return m_builder.build(); }
void append(StringView pattern)
{
GenericLexer lexer { pattern };
while (!lexer.is_eof()) {
// FIXME: It is a bit inconvinient, that 'consume_until' also consumes the 'stop' character, this makes
// the method less generic because there is no way to check if the 'stop' character ever appeared.
const auto consume_until_without_consuming_stop_character = [&](char stop) {
return lexer.consume_while([&](char ch) { return ch != stop; });
};
m_builder.append(consume_until_without_consuming_stop_character(m_opening));
if (lexer.consume_specific(m_opening)) {
const auto placeholder = consume_until_without_consuming_stop_character(m_closing);
if (!lexer.consume_specific(m_closing))
ASSERT_NOT_REACHED();
m_builder.append(get(placeholder));
} else {
ASSERT(lexer.is_eof());
}
}
}
private:
StringBuilder& m_builder;
MappingType m_mapping;
char m_opening, m_closing;
};
}
using AK::SourceGenerator;