-- @name		FPath
-- @version		1.0
-- @authors		Frédéric Jouault
-- @date		20080124
-- @description	Concrete syntax of the FPath Fractal navigation language.

-- The different sections of a TCS model have been enclosed between BEGIN and END
-- comments below. Additional information is provided below each BEGIN comment.
-- The main sections of interest are "Class templates", and
-- "Operator table" (the latter only for DSLs using operators).
syntax FPath {

-- BEGIN Primitive templates
-- Specifies representation of primitive types.
-- Only needs modification when default lexer is not satisfactory.
-- Generally modified along with the lexer.
	primitiveTemplate identifier for String default using NAME:
		value = "%token%";

	primitiveTemplate stringSymbol for String using STRING:
		value = "%token%",
		serializer="'\'' + %value%.toCString() + '\''";

	primitiveTemplate floatSymbol for Double default using FLOAT:
		value = "Double.valueOf(%token%)";
-- END Primitive templates

-- BEGIN Class templates
-- Specifies representation of classes.
-- This is the main section to work on.
	template Expression main abstract operatored;
	
	template ContextExp
		:	"."
		;
		
	template VariableExp
		:	"$" name
		;

	template FunctionCallExp
		:	name "(" arguments{separator = ","} ")"
		;

	template NumberExp
		:	'value'
		;

	template StringExp
		:	'value'{as = stringSymbol}
		;

	operatorTemplate PathExp(operators = opSlash, source = initialNodeSet)
		:	steps{separator = "/"}
		;

	operatorTemplate BinaryOperatorExp(operators =
			opMul opDiv
			opPlus opMinus2
			opLt opGt opLe opGe opEq opNe
			opAnd opOr
			, source = 'left', storeOpTo = operator, storeRightTo = 'right'
		);

	operatorTemplate UnaryOperatorExp(operators =
			opNot opMinus1
			, source = operand, storeOpTo = operator
		);
		
	template Step
		:	axis "::" test (isDefined(predicates) ? "[" predicates{separator = "]" "["} "]")
		;

	template Test abstract;
	
	template WildcardTest
		:	"*"
		;

	template NameTest
		:	name
		;

	enumerationTemplate Axis
		:	#component				= "component",
			#'internal-interface'	= "internal-interface",
			#interface				= "interface",
			#attribute				= "attribute",
			#binding				= "binding",
			#child					= "child",
			#parent					= "parent",
			#descendant				= "descendant",
			#ancestor				= "ancestor",
			#sibling				= "sibling",
			#'descendant-or-self'	= "descendant-or-self",
			#'ancestor-or-self' 	= "ancestor-or-self",
			#'sibling-or-self'		= "sibling-or-self"
		;
-- END Class templates

-- BEGIN Special symbols
-- Possible modifications:
--	- Addition of new symbols.
--	- Modification of spaces information.
--	- Removal of unused symbols so that using these symbols results in lexical
--	error rather than parsing error.
	symbols {
		lsquare		= "[";
		rsquare		= "]"	: rightSpace;
		excl		= "!";
		coma		= ","	: leftNone, rightSpace;
		lparen		= "(";
		rparen		= ")"	: leftNone, rightSpace;
		lcurly		= "{"	: leftSpace;
		rcurly		= "}"	: leftNone, rightSpace;
		semi		= ";"	: leftNone, rightSpace;
		colon		= ":"	: leftSpace, rightSpace;
		coloncolon	= "::"	: leftNone, rightNone;
		pipe		= "|"	: leftSpace, rightSpace;
		sharp		= "#"	: leftSpace;
		qmark		= "?";

		-- operator symbols
		point		= "."	: leftNone;
		rarrow		= "->"	: leftNone;
		minus		= "-"	: leftSpace, rightSpace;
		star		= "*"	: leftSpace, rightSpace;
		slash		= "/"	: leftSpace, rightSpace;
		plus		= "+"	: leftSpace, rightSpace;
		eq			= "="	: leftSpace, rightSpace;
		eqeq		= "=="	: leftSpace, rightSpace;
		gt			= ">"	: leftSpace, rightSpace;
		lt			= "<"	: leftSpace, rightSpace;
		ge			= ">="	: leftSpace, rightSpace;
		le			= "<="	: leftSpace, rightSpace;
		ne			= "<>"	: leftSpace, rightSpace;
		larrow		= "<-"	: leftSpace, rightSpace;
	}
-- END Special symbols

-- BEGIN Operator table
-- Defines all operators with their priority, arity, and associativity.
-- All defined operators must be used in operator templates.
	operators {
		priority 0 {	-- highest priority
			opSlash = slash, 2;
		}
		
		priority 1 {
			opNot = "not", 1;
			opMinus1 = minus, 1;
		}
		
		priority 2 {
			opMul = star, 2;
			opDiv = "div", 2;
		}

		priority 3 {
			opPlus = plus, 2;
			opMinus2 = minus, 2;
		}

		priority 4 {
			opLt = lt, 2;
			opGt = gt, 2;
			opLe = le, 2;
			opGe = ge, 2;
			opEq = eqeq, 2;
			opNe = ne, 2;
		}

		priority 5 {
			opAnd = "and", 2;
			opOr = "or", 2;
		}
	}
-- END Operator table


-- BEGIN Lexer
-- Specifies the lexical entities.
-- Only needs modification when default lexer is not satisfactory.
-- Generally modified along with Primitive templates.
	token COMMENT	: endOfLine(start = "--");

	lexer = "
%options testLiterals = false;

NL
	:	(	'\\r' '\\n'
		|	'\\n' '\\r'	//Improbable
		|	'\\r'
		|	'\\n'
		)
	{newline();}
	;

WS
	:	(	' '
		|	'\\t'
		)
	;

%protected
DIGIT
	:	'0'..'9'
	;

%protected
ALPHA
	:	'a'..'z'
	|	'A'..'Z'
	|	'_'
	//For Unicode compatibility (from 0000 to 00ff)
	|	'\\u00C0' .. '\\u00D6'
	|	'\\u00D8' .. '\\u00F6'
	|	'\\u00F8' .. '\\u00FF'
	;

%protected
SNAME
%v2	options {
%v2		testLiterals = true;
%v2	}
	:	(ALPHA) (ALPHA | DIGIT)*
;

NAME
	:	(
%v3			SNAME
%v2			s:SNAME {if(s.getType() != SNAME) $setType(s.getType());}
		|	'\"'!
			(	ESC
			|	'\\n' {newline();}
			|	~('\\\\'|'\\\"'|'\\n')
			)*
			'\"'!
%v3			{setText(ei.unescapeString(getText(), 1));}
		)
	;

%v3	FLOAT	:	DIGIT+ ('.' DIGIT*)?	;

%protected
ESC
	:	'\\\\'!
		(	'n' %v2{%setText(\"\\n\");}
		|	'r' %v2{%setText(\"\\r\");}
		|	't' %v2{%setText(\"\\t\");}
		|	'b' %v2{%setText(\"\\b\");}
		|	'f' %v2{%setText(\"\\f\");}
		|	'\"' %v2{%setText(\"\\\"\");}
		|	'\\'' %v2{%setText(\"\\'\");}
		|	'\\\\' %v2{%setText(\"\\\\\");}
		|	(
				('0'..'3')
				(
%v2					options {
%v2						warnWhenFollowAmbig = false;
%v2					}
				:	('0'..'7')
					(
%v2						options {
%v2							warnWhenFollowAmbig = false;
%v2						}
					:	'0'..'7'
					)?
				)?
			|	('4'..'7')
				(
%v2					options {
%v2						warnWhenFollowAmbig = false;
%v2					}
				:	('0'..'7')
				)?
			)
				{
%v2					String s = %getText;
%v2					int i;
%v2					int ret = 0;
%v2					String ans;
%v2					for (i=0; i<s.length(); ++i)
%v2						ret = ret*8 + s.charAt(i) - '0';
%v2					ans = String.valueOf((char) ret);
%v2					%setText(ans);
				}
		)
	;

STRING
	:	'\\''!
		(	ESC
		|	'\\n' {newline();}
		|	~('\\\\'|'\\''|'\\n')
		)*
		'\\''!
%v3			{setText(ei.unescapeString(getText(), 1));}
	;

	";
-- END Lexer

}