Xtext - Operator Precedence and Associativity

XtextOperators.md

Precedence

  Expression returns Expression: Multiplication;
  Multiplication returns Expression: Addition => ({Multiplication.left = current} '*' right = Addition)*;
  Addition returns Expression: Primary => ({Addition.left = current} '+' right = Primary)*;
  Primary returns Expression: Integer | '(' Expression ')';
  Integer returns Integer: value = INT;

Associativity

Left

  Expression returns Expression: Addition;
  Addition returns Expression: Integer => ({Addition.left = current) '+' right = Integer)*;
  Integer returns Integer: value = INT;

Right

  Expression returns Expression: Addition;
  Addition returns Expression: Integer => ({Addition.left = current} '+' right = Addition)?;
  Integer returns Integer: value = INT;

None

  Expression returns Expression: Addition;
  Addition returns Expression: Integer => ({Addition.left = current} '+' right = Integer)?;
  Integer returns Integer: value = INT;