/*
* opencog/atoms/core/QuoteLink.h
*
* Copyright (C) 2025 BrainyBlaze Dynamics, LLC
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License v3 as
* published by the Free Software Foundation and including the exceptions
* at http://opencog.org/wiki/Licenses
*
* This program 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.
*/
#ifndef _OPENCOG_QUOTE_LINK_H
#define _OPENCOG_QUOTE_LINK_H
#include <opencog/atoms/base/Link.h>
namespace opencog
{
/** \addtogroup grp_atomspace
* @{
*/
/// The QuoteLink is used to prevent evaluation of its contents during
/// pattern matching and during beta reduction. To unwrap the quoted
/// expression ("to consume the quotes"), it is enough to execute the
/// QuoteLink: the quoted content will be returned. Matching nested
/// Unquotes are consumed in the process.
///
/// For example:
///
/// (Quote (Concept "foo"))
///
/// when executed returns:
///
/// (Concept "foo")
///
/// And:
///
/// (Quote (List (Unquote (Concept "bar"))))
///
/// when executed returns:
///
/// (List (Concept "bar"))
///
class QuoteLink : public Link
{
public:
QuoteLink(const HandleSeq&&, Type=QUOTE_LINK);
QuoteLink(const QuoteLink&) = delete;
QuoteLink& operator=(const QuoteLink&) = delete;
virtual bool is_executable() const { return true; }
virtual ValuePtr execute(AtomSpace*, bool);
static Handle factory(const Handle&);
};
LINK_PTR_DECL(QuoteLink)
#define createQuoteLink CREATE_DECL(QuoteLink)
/** @}*/
}
#endif // _OPENCOG_QUOTE_LINK_H