// Copyright (C) 2015 xaizek <xaizek@posteo.net>
//
// This file is part of dit.
//
// dit is free software: you can redistribute it and/or modify
// it under the terms of version 3 of the GNU Affero General Public
// License as published by the Free Software Foundation.
//
// dit is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with dit. If not, see <http://www.gnu.org/licenses/>.
#ifndef DIT__ITEMFILTER_HPP__
#define DIT__ITEMFILTER_HPP__
#include <functional>
#include <string>
#include <vector>
struct Cond;
class Item;
/**
* @brief Checks items for satisfying set of constraints.
*
* Supported operations include: ==, !=.
* Form of each expression: <field> <op> <value>.
*/
class ItemFilter
{
/**
* @brief Type of function that is used to query field value.
*
* A field can be expanded to zero, one or multiple values and each value
* will be matched individually.
*/
using accessor_f = std::vector<std::string>(const std::string &key);
public:
/**
* @brief Constructs the filter out of conditions in textual form.
*
* @param exprs Set of expressions to check against.
*/
explicit ItemFilter(const std::vector<std::string> &exprs);
/**
* @brief Constructs the filter out of single condition.
*
* @param cond
*/
explicit ItemFilter(Cond cond);
/**
* @brief Emit destructor code in corresponding source file.
*/
~ItemFilter();
public:
/**
* @brief Checks whether given item passes the filter.
*
* @param item Item to check for compliance.
*
* @returns @c true if it passes, and @c false otherwise.
*/
bool passes(Item &item) const;
/**
* @brief Checks whether item represented by its fields passes the filter.
*
* This is a generalized version, which allows for different representations
* of items.
*
* @param accessor Accessor of item data (by field name).
*
* @returns @c true if it passes, and @c false otherwise.
*/
bool passes(const std::function<accessor_f> &accessor) const;
/**
* @brief Checks whether item represented by its fields passes the filter.
*
* @param accessor Accessor of item data (by field name).
* @param error[out] Storage for error message.
*
* @returns @c true if it passes, and @c false otherwise.
*/
bool passes(const std::function<accessor_f> &accessor,
std::string &error) const;
private:
/**
* @brief Set of constraints.
*/
std::vector<Cond> conds;
};
#endif // DIT__ITEMFILTER_HPP__
Before first commit, do not forget to setup your git environment:
git config --global user.name "your_name_here"
git config --global user.email "your@email_here"
Clone this repository using HTTP(S):
git clone https://code.reversed.top/user/xaizek/dit
Clone this repository using ssh (do not forget to upload a key first):
git clone ssh://rocketgit@code.reversed.top/user/xaizek/dit
You are allowed to anonymously push to this repository.
This means that your pushed commits will automatically be transformed into a
pull request:
... clone the repository ...
... make some changes and some commits ...
git push origin master