ezc/src/funinfo.h

/*
 * This file is a part of EZC -- Easy templating in C++
 * and is distributed under the (new) BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2007-2012, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *    
 *  * 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.
 *    
 *  * Neither the name Tomasz Sowa nor the names of contributors to this
 *    project may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * 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 OWNER 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.
 */


#ifndef headerfile_ezc_funinfo
#define headerfile_ezc_funinfo

#include <vector>



namespace Ezc
{


/*
	a base class for your own function data class
*/
struct FunData
{
	FunData()
	{
	}

	virtual ~FunData()
	{
	}
};



/*
	a generator's stack item
	each statement ([if ...] [for ...] [normal_funcion]) have its own stack item
	iter     - is used only in [for...] - it is the current iteration (start from zero)
	           for other statements it is always zero
	fun_data - by default this is null pointer, you can set it to a pointer
	           to an object derived from FunData
			   (this have sense only in [for...] statement because in other statements
			   this object would be immediately removed)
	remove   - when true it means that object pointing by fun_data should be automatically
	           removed -- (by using delete fun_data)
*/
struct Stack
{
	size_t iter;
	FunData * fun_data;
	bool remove;

	Stack()
	{
		Clear();
	}

	void Clear()
	{
		iter     = 0;
		fun_data = 0;
		remove   = true;
	}
};



template<class StreamType>
struct FunInfo
{
	// output stream
	StreamType & out;

	// the out stream is treated in case sensitive
	// used only in [is...] statements
	// default: true
	bool case_sensitive;

	// table of parameters
	// the table can be empty
	std::vector<std::wstring> & params;

	// the first parameter
	// you can always use it even if there is not any parameters (params is empty)
	// in such a way the reference points to an empty string
	const std::wstring & par;

	// an input stream used in [filter] statement
	// if there is other statement than [filter] then this is an empty stream
	const StreamType & in;

	// indicates that this function is from [for ...] statement
	bool is_for;

	// indicates that this function is from [if ...] statement
	// is true for all kind of if's: if-one, if-any, if-no....
	bool is_if;

	// indicates that this function is from [is ...] or [is-no ...] statements
	bool is_is;

	// indicates that this funcion is a normal statement e.g.: [funcion_name]
	bool is_normal;

	// indicates that this function is from a filter statement [filter ...]
	bool is_filter;

	// a pointer to a stack's item from generator's stack
	// it is never null
	// each function has a new stack item
	// on this stack you have iter (description below) and fun_data pointer
	// you can assign to it your own object derived from FunData
	Stack * stack;

	// the same as stack->iter (this is mainly for backward compatibility)
	// it indicates the number of a current iteration for the [for] statement (the first iteration is 0)
	// for other statements than [for] this is always zero
	size_t iter;

	// return value from a user's function (default false if not set directly by the function)
	// for a variable it is set to true if the variable is not empty
	bool res;


	// arguments: output_stream, table_of_parameters, the_first_parameter
	FunInfo(StreamType & o,
			std::vector<std::wstring> & pars,
			const std::wstring & first_par,
			const StreamType & i) : out(o), params(pars), par(first_par), in(i)
	{
		Clear();
	}


	void Clear()
	{
		res					= false;	// result is false by default
		is_for				= false;
		is_if				= false;
		is_is				= false;
		is_normal			= false;
		is_filter			= false;
		stack				= 0;
		iter				= 0;
		case_sensitive		= true;
	}
};




} // namespace Ezc


#endif