reference_comparand.h

/*
 Copyright (c) 2013 by ScaleOut Software, Inc.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
*/ 

#pragma once

#include <string>
#include <vector>
#include <stdint.h>
#include <boost/shared_ptr.hpp>

#include "soss_client/filter.h"
#include "soss_client/query_expression.h"
#include "soss_client/expression_comparand.h"

namespace sosscli {

class ValueComparand;
class QueryExpression;

namespace internal {
 class ComparisonExpression;
}

class ReferenceComparand : public ExpressionComparand
{
public:
 // We use 'explicit' here so that C++ implicit type conversion will default to converting a string to a ValueOperand
 // rather than a ReferenceOperand. As a result, an expression like ReferenceComparand("field") == "value" is no
 // longer ambiguous. It also means that if you want to compare two field values on the server you'd need to write
 // your expression as 
 //
 // ReferenceComparand("field_1") == ReferenceComparand("field_2")

 explicit ReferenceComparand(std::string const & field_name);

 explicit ReferenceComparand(const char * field_name);

 Filter operator ==(ValueComparand const & value);

 Filter operator ==(ReferenceComparand const & field);

 Filter operator !=(ValueComparand const & value);

 Filter operator !=(ReferenceComparand const & field);

 Filter operator >(ValueComparand const & value);

 Filter operator >(ReferenceComparand const & field);

 Filter operator >=(ValueComparand const & value);

 Filter operator >=(ReferenceComparand const & field);

 Filter operator <(ValueComparand const & value);

 Filter operator <(ReferenceComparand const & field);

 Filter operator <=(ValueComparand const & value);

 Filter operator <=(ReferenceComparand const & field);

 Filter contains(ValueComparand const & value);

 Filter contains(ReferenceComparand const & ref);

 // TODO: HasAnyTag, HasAllTags, HasTags

 std::string const & field_name() const;

 virtual void accept(QueryExpression::Visitor & v) const;

private:
 std::string field_name_;
};


}