demotool/opast.hh

#pragma once
//#ifndef REAL_BUILD
# include "externals.hh"
//#endif

#include <ebcl/SRDData.hh>


namespace opast {

using namespace ebcl;

class T_RootNode;

class A_Node
{
    public:
	enum E_Type {
		ROOT ,
		//
		DECL_INIT ,
		DECL_FRAME ,
		DECL_FN ,
		//
		OP_SET ,
		//
		EXPR_ADD ,
		EXPR_MUL ,
		EXPR_SUB ,
		EXPR_DIV ,
		EXPR_VAR ,
		EXPR_CONST ,
	};

    private:
	const E_Type type_;
	A_Node* const parent_;
	T_SRDLocation location_;

    protected:
	explicit A_Node( const E_Type type ,
			A_Node* const parent ) noexcept;

    public:
	virtual ~A_Node( ) = 0;

	E_Type type( ) const noexcept
		{ return type_; }

	T_SRDLocation& location( ) noexcept
		{ return location_; }
	T_SRDLocation const& location( ) const noexcept
		{ return location_; }

	A_Node& parent( ) const noexcept
		{ assert( parent_ ); return *parent_; }

	T_RootNode& root( ) const noexcept;
};

/*----------------------------------------------------------------------------*/

// Function-like nodes
class A_FuncNode : public A_Node
{
    private:
	T_String name_;

    protected:
	// For init or frame entry points.
	// isInit = true => init entry point
	// isInit = false => frame entry point
	explicit A_FuncNode( bool isInit ,
			T_RootNode* const parent ) noexcept;

	// For normal functions
	explicit A_FuncNode( T_String const& name ,
			T_RootNode* const parent ) noexcept;

    public:
	T_String const& name( ) const noexcept
		{ return name_; }
};

// Root node, keeps track of the whole tree and related data (function table,
// assets...)
class T_RootNode : public A_Node
{
    private:
	T_ObjectTable< T_String , T_OwnPtr< A_FuncNode > > functions_;

    public:
	T_RootNode( ) noexcept;

	// Return type for addFunction. We'll always return a reference to a
	// function node (which may or may not be the same as the initial one,
	// if there were duplicates), and we'll return the location of the
	// initial function in the case of a duplicate.
	struct T_AddFunctionResult
	{
		A_FuncNode& function;
		T_Optional< T_SRDLocation > dupLocation;

		T_AddFunctionResult( A_FuncNode& function ) noexcept
			: function{ function } , dupLocation{}
		{}

		T_AddFunctionResult( A_FuncNode& function ,
				T_SRDLocation const& dupLocation ) noexcept
			: function{ function } , dupLocation{ dupLocation }
		{}
	};

	// Attempts to add a function. If the function is already present in
	// the table, the result will be set up with the previous declaration's
	// location, and the specified function will not be modified (a duplicate
	// entry will be added to the table instead).
	T_AddFunctionResult addFunction(
			T_OwnPtr< A_FuncNode >& function ) noexcept;
};

/*----------------------------------------------------------------------------*/

// Init & frame functions
class T_SpecialFuncNode : public A_FuncNode
{
    public:
	T_SpecialFuncNode(
			bool isInit ,
			T_RootNode& parent ) noexcept;
};

// Normal functions
class T_FuncNode : public A_FuncNode
{
    private:
	T_AutoArray< T_String , 8 > argNames_;
	T_AutoArray< T_SRDLocation , 8 > argLocations_;

    public:
	T_FuncNode( T_String const& name ,
			T_RootNode& parent ) noexcept;

	// Add an argument. If the argument is a duplicate, return the location
	// of the initial argument.
	T_Optional< T_SRDLocation > addArgument(
			T_SRDToken const& token ) noexcept;
};

/*----------------------------------------------------------------------------*/

class T_Parser : public A_PrivateImplementation
{
    private:
	T_Array< T_SRDError > errors_;
	T_OwnPtr< T_RootNode > rootNode_;

    public:
	T_Parser( ) noexcept;

	bool parse( T_SRDList const& input ) noexcept;

	T_Array< T_SRDError > const& errors( ) const noexcept
		{ return errors_; }
	T_OwnPtr< T_RootNode > result( ) noexcept
		{ return std::move( rootNode_ ); }
};


} // namespace opast