construct/include/ircd/globular.h

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2019 Jason Volk <jason@zemos.net>
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice is present in all copies. The
// full license for this software is available in the LICENSE file.

#pragma once
#define HAVE_IRCD_GLOBULAR_H

namespace ircd
{
	// Globular ('*' and '?') expression utils.
	struct globular_match;
	struct globular_equals;
}

/// Globular equals. This allows either side of the comparison to include '*'
/// and '?' characters and equality of the string expressions will be
/// determined.
struct ircd::globular_equals
{
	using is_transparent = std::true_type;

	bool s;

	operator const bool &() const
	{
		return s;
	}

	bool operator()(const string_view &a, const string_view &b) const;

	template<class A,
	         class B>
	globular_equals(A&& a, B&& b)
	:s{operator()(std::forward<A>(a), std::forward<B>(b))}
	{}

	globular_equals() = default;
};

/// Globular match. Similar to globular_equals but only one side of the
/// comparison is considered to be the expression with '*' and '?' characters.
/// The expression string is passed at construction. The comparison inputs are
/// treated as non-expression strings. This allows for greater optimization
/// than globular_equals.
struct ircd::globular_match
{
	string_view expr;
	bool s;

	operator const bool &() const
	{
		return s;
	}

	bool operator()(const string_view &a) const;

	globular_match(const string_view &expr)
	:expr{expr}
	{}

	template<class A>
	globular_match(const string_view &expr, A&& a)
	:expr{expr}
	,s{operator()(std::forward<A>(a))}
	{}

	globular_match() = default;
};