code: public final void ruleXPrimaryExpression() throws RecognitionException {
  
          		int stackSize = keepStackSize();
          	
          try {
              // InternalXbase.g:671:2: ( ( ( rule__XPrimaryExpression__Alternatives ) ) )
              // InternalXbase.g:672:2: ( ( rule__XPrimaryExpression__Alternatives ) )
              {
              // InternalXbase.g:672:2: ( ( rule__XPrimaryExpression__Alternatives ) )
              // InternalXbase.g:673:3: ( rule__XPrimaryExpression__Alternatives )
              {
              if ( state.backtracking==0 ) {
                 before(grammarAccess.getXPrimaryExpressionAccess().getAlternatives()); 
              }
              // InternalXbase.g:674:3: ( rule__XPrimaryExpression__Alternatives )
              // InternalXbase.g:674:4: rule__XPrimaryExpression__Alternatives
              {
              pushFollow(FOLLOW_2);
              rule__XPrimaryExpression__Alternatives();
  
              state._fsp--;
              if (state.failed) return ;
  
              }
  
              if ( state.backtracking==0 ) {
                 after(grammarAccess.getXPrimaryExpressionAccess().getAlternatives()); 
              }
  
              }
  
  
              }
  
          }
          catch (RecognitionException re) {
              reportError(re);
              recover(input,re);
          }
          finally {
  
              	restoreStackSize(stackSize);
  
          }
          return ;
      }
docs: InternalXbase.g:667:1: ruleXPrimaryExpression : ( ( rule__XPrimaryExpression__Alternatives ) ) ;