Merge pull request #33 from UnB-CIC/feature/oberon-concrete-syntax

Feature/oberon concrete syntax

sample-code/oberon/src/lang/oberon/ConcreteSyntax.rsc

@@ -0,0 +1,199 @@
+module lang::oberon::ConcreteSyntax
+
+/*
+	Based on https://github.com/kesarevs/oberon-antlr/blob/master/oberon/Oberon.g4
+	Reference: https://inf.ethz.ch/personal/wirth/Oberon/Oberon07.Report.pdf
+*/
+
+// TODO: WS : ( ' ' | '\t' | '\r' | '\n') -> skip;
+// TODO: COMMENT : '(*' .*? '*)' -> skip;
+
+lexical PERIOD = "." ;
+lexical RANGESEP = "..";
+lexical SEMI = ";";
+lexical UPCHAR = "^";
+lexical COLON = ":";
+lexical COMMA = ",";
+lexical NOT = "~";
+
+lexical UNEQUAL = "#";
+lexical LESS = "\<"; // Escape tá certo?
+lexical GREATER = "\>";  // Escape
+lexical LESSOREQ = "\<=";  // Escape
+lexical GREATEROREQ = "\>=";  // Escape
+lexical IN = "IN";
+lexical EQUAL = "=";
+
+lexical ASSIGN = ":=";
+lexical DIV = "DIV" ;
+lexical DIVISION = "/";
+lexical ET = "&";
+lexical MINUS = "-";
+lexical MOD = "MOD";
+lexical MULT = "*";
+lexical OR = "|";
+lexical PLUS = "+";
+
+syntax AddOperator
+	= op: PLUS
+    | op: MINUS 
+    | op: OR
+    ;
+
+syntax Relation
+	= op: EQUAL 
+    | op: UNEQUAL 
+    | op: LESS 
+    | op: GREATER 
+    | op: LESSOREQ 
+    | op: GREATEROREQ 
+    | op: IN
+    ;
+
+syntax MulOperator
+	= op: MULT 
+    | op: DIVISION
+    | op: DIV 
+    | op: MOD 
+    | op: ET
+    ;
+
+lexical ID = [a-zA-Z][a-zA-Z_0-9]*;
+
+lexical INT = [0-9]+ ;
+lexical REAL = [0-9]+[.][0-9]+ ;
+lexical STRING = [\"]*[\"];
+syntax NOT_FACTOR = NOT Factor;
+syntax NIL = "NIL";
+syntax Boolean
+ 	= "TRUE"
+  	| "FALSE"
+  	;
+
+syntax Factor
+	= int_factor: INT
+	| real_factor: REAL
+	| boolean_factor: Boolean
+	| string_factor: STRING
+	| nil_type: NIL
+	| set_factor: SET
+	| designator_factor: Designator
+	| simpleExpression_factor: "(" SimpleExpression ")"
+	| procedurecall_factor: ProcedureCall
+	| NOT_FACTOR
+	;
+
+syntax Designator = Qualident DesignatorArgs;
+syntax DesignatorArgs = "[" Explist "]" | UPCHAR; // TODO: Existe construção isArray ?
+
+lexical Qualident = (ID '.')* ID;
+
+syntax Explist = Expression (COMMA Expression)*;
+
+syntax Expression = SimpleExpression (Relation SimpleExpression)?;
+syntax SimpleExpression = MINUS? Term (AddOperator Term)*;
+syntax Term = Factor (MulOperator Factor)*;
+
+syntax ProcedureCall = ID ActualParameters;
+syntax ActualParameters = "(" Explist? ")";
+
+syntax CaseLabelList = CaseLabels (COMMA CaseLabels)* ;
+syntax CaseLabels = Expression (RANGESEP Expression)?;
+
+syntax Set = '{' CaseLabelList? '}' ;
+
+syntax DeclarationSequence = DeclarationOptions+;
+syntax DeclarationOptions = "CONST" (ConstantDeclaration SEMI)* | "VAR" (VariableDeclaration SEMI)*;
+
+syntax VariableDeclaration = IdentList COLON Type;
+syntax ConstantDeclaration = IdentDef EQUAL Expression;
+
+syntax IdentDef = ID;
+syntax IdentList = IdentDef (COMMA IdentDef)*;
+
+syntax Type = BaseTypes; // TODO: | isArr=arraytype;
+syntax BaseTypes = "INTEGER" | "REAL" | "BOOLEAN";
+
+syntax ArrayType = "ARRAY" ExplList "OF" Type;
+syntax RecordType = "RECORD" ('(' Qualident ')')? FieldListSequence "END" ;
+syntax PointerType = "POINTER" "TO" Type ;
+syntax ProcedureType = "PROCEDURE" FormalParameters? ;
+
+syntax FieldList = (IdentList COLON Type)?;
+syntax FieldListSequence = FieldList (SEMI FieldList);
+
+syntax FpSection = "VAR"? IdList COLON Type ;
+syntax Params = FpSection (SEMI FpSection)*;
+syntax FormalParameters = "(" Params? ")" (COLON Type)? ;
+
+syntax ProcedureDeclaration = ProcedureHeading SEMI ProcedureBody ID;
+syntax ProcedureHeading = "PROCEDURE" IdentDef "*"? FormalParameters?;
+syntax ProcedureBody = DeclarationSequence? ("BEGIN" StatementSequence)? "END";
+
+syntax WhileStatement = "WHILE" Expression "DO" StatementSequence "END";
+syntax RepeatStatement = "REPEAT" StatementSequence "UNTIL" Expression;
+syntax LoopStatement = "LOOP" StatementSequence "END";
+
+syntax IfStatement = "IF" Expression "THEN" StatementSequence ("ELSIF" Expression "THEN" StatementSequence)* ("ELSE" StatementSequence)? "END";
+syntax CaseStatement = "CASE" Expression "OF" CaseItem ("|" CaseItem)* ("ELSE" StatementSequence)? "END";
+syntax CaseItem = CaseLabelList COLON StatementSequence;
+syntax CaseLabelList = CaseLabels (COMMA CaseLabels)*;
+syntax CaseLabels = Expression (RANGESEP Expression)?;
+
+syntax Module = "MODULE" ID SEMI DeclarationSequence? ModuleDeclarations* ("BEGIN" StatementSequence)? "END" ID PERIOD ;
+syntax ModuleDeclarations = ProcedureDeclaration SEMI | ForwardFeclaration SEMI;
+syntax ImportList = "IMPORT" ImportItem (COMMA ImportItem)* SEMI;
+syntax ImportItem = ID (ASSIGN ID)?;
+
+syntax ForwardDeclaration = "PROCEDURE" UPCHAR? ID MULT? FormalParameters?;
+
+syntax StatementSequence = Statement SEMI (Statement SEMI)* ;
+
+syntax Statement = Assignment
+        | ProcedureCall
+        | IfStatement
+        | CaseStatement
+        | WhileStatement
+        | RepeatStatement
+        | LoopStatement
+        | WithStatement 
+        | "EXIT"
+        | "RETURN" Expression?
+        ;
+
+syntax WithStatement = "WITH" Qualident COLON Qualident "DO" StatementSequence "END";
+
+keyword Keywords
+	= "ARRAY"
+	| "BEGIN"
+	| "CASE"
+	| "CONST"
+	| "DO"
+	| "ELSE"
+	| "ELSIF"
+	| "END"
+	| "EXIT"
+	| "IF"
+	| "IMPORT"
+	| "LOOP"
+	| "MODULE"
+	| "NIL"
+	| "OF"
+	| "POINTER"
+	| "PROCEDURE"
+	| "RECORD"
+	| "REPEAT"
+	| "RETURN"
+	| "THEN"
+	| "TO"
+	| "TYPE"
+	| "UNTIL"
+	| "VAR"
+	| "WHILE"
+	| "WITH"
+	| "TRUE"
+	| "FALSE"
+	| "PRINT"
+	| "INTEGER"
+	| "REAL"
+	| "BOOLEAN";