diff --git a/Source/Decaf.g4 b/Source/Decaf.g4
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+grammar Decaf;
+
+program: classdecl+;
+
+//class identifier{...}
+classdecl: (AccessModifierPrivate|AccessModifierPublic|AccessModifierProtected)? 'class' Identifier OpenCurlyBracket (constuctorDecl|fieldDecl|methodDecl)* ClosedCurlyBracket;
+constuctorDecl: (AccessModifierPrivate|AccessModifierPublic|AccessModifierProtected)? Identifier OpenRoundBracket parameterList? ClosedRoundBracket block; //Maybe not needed
+
+//Method and FieldVar
+methodDecl: MainMethodDecl block | (AccessModifierPrivate|AccessModifierPublic|AccessModifierProtected)? (type | Void) Identifier OpenRoundBracket parameterList? ClosedRoundBracket block;
+fieldDecl: (AccessModifierPrivate|AccessModifierPublic|AccessModifierProtected)? type Identifier Semicolon;
+
+//Parameters
+parameterList: parameter(Comma parameter)*;
+parameter: type Identifier;
+
+//property, object.a, 3+1, a = 3
+expression: subExpression | binaryExpr;
+//subExpression to dissolve left-recusion
+subExpression: This | Identifier | instVar  | value | stmtExpr | notExpr | OpenRoundBracket expression ClosedRoundBracket;
+notExpr: Not expression;
+assignableExpr: Identifier | instVar;
+instVar: This Dot Identifier | (This Dot)? (Identifier Dot)+ Identifier;
+
+//.trim().toLength().toLowerCase().count ...
+methodCall: receiver? receivingMethod* Identifier OpenRoundBracket argumentList ClosedRoundBracket;
+argumentList: expression? | expression (Comma expression)*?;
+
+binaryExpr: calcExpr | nonCalcExpr;
+
+calcExpr: calcExpr LineOperator dotExpr | dotExpr;
+dotExpr: dotExpr DotOperator dotSubExpr | dotSubExpr;
+dotSubExpr: IntValue | Identifier | instVar | methodCall | OpenRoundBracket calcExpr ClosedRoundBracket;
+nonCalcExpr: subExpression nonCalcOperator expression;
+nonCalcOperator: LogicalOpertor | ComparisonOperator;
+
+//Statement but also expression
+//a = expr, new Object(), method(param1)
+stmtExpr: assign | newDecl | methodCall;
+
+//Statements
+//int a, {...}, while(a > 10){...}, if(...){...} else if{...} else{...}
+statement: returnStmt Semicolon | localVarDecl Semicolon | block | whileStmt | ifElseStmt | stmtExpr Semicolon;
+returnStmt: Return (expression)?;
+localVarDecl: type Identifier (Assign expression)?;
+block: OpenCurlyBracket statement* ClosedCurlyBracket;
+whileStmt: While OpenRoundBracket expression ClosedRoundBracket block;
+ifElseStmt: ifStmt elseStmt?;
+ifStmt: If OpenRoundBracket expression ClosedRoundBracket statement;
+elseStmt: Else statement;
+assign: assignableExpr Assign expression;
+newDecl: New Identifier OpenRoundBracket argumentList ClosedRoundBracket;
+receiver: ((This | instVar | newDecl | Identifier) Dot);
+receivingMethod: Identifier OpenRoundBracket argumentList ClosedRoundBracket Dot;
+type: Int | Boolean  | Char | Identifier;
+value: IntValue | BooleanValue | CharValue | NullValue;
+
+//Access modifier
+AccessModifierPublic    : 'public' ;
+AccessModifierPrivate   : 'private';
+AccessModifierProtected : 'protected';
+MainMethodDecl          : 'public static void main(String[] args)';
+
+//Types
+Void    : 'void';
+Int     : 'int';
+Boolean : 'bool';
+Char    : 'char';
+
+//Operators
+DotOperator         : Multipilkation | Division | Modulo;
+LineOperator        : Plus | Minus;
+ComparisonOperator  : Greater | Less | GreaterEqual | LessEqual | Equal | NotEqual;
+LogicalOpertor      : And | Or;
+
+Assign          : '=';
+Minus           : '-';
+Plus            : '+';
+Multipilkation  : '*';
+Division        : '/';
+Modulo          : '%';
+Greater         : '>';
+Less            : '<';
+GreaterEqual    : '>=';
+LessEqual       : '<=';
+Equal           : '==';
+NotEqual        : '!=';
+Not             : '!';
+And             : '&&';
+Or              : '||';
+
+//Symbols
+Dot                 : '.';
+OpenRoundBracket    : '(';
+ClosedRoundBracket  : ')';
+OpenCurlyBracket    : '{';
+ClosedCurlyBracket  : '}';
+Semicolon           : ';';
+Comma               : ',';
+
+//Keywords
+Class   : 'class';
+This    : 'this';
+While   : 'while';
+If      : 'if';
+Else    : 'else';
+For     : 'for';
+Return  : 'return';
+New     : 'new';
+
+//Identifier
+fragment Alpabetic : [a-zA-Z];
+fragment Numeric: [0-9];
+fragment ValidIdentSymbols : Alpabetic|Numeric|'$'|'_';
+Identifier: Alpabetic ValidIdentSymbols*;
+
+//Values
+IntValue : ('+'|'-')*[0-9]+;
+CharValue: '\''~[\r\n]?'\'';
+BooleanValue: 'true'|'false';
+NullValue: 'null';
+
+//Whitespace? Right into the trash it gooeesss
+WS : [ \t\r\n] -> skip;
+