code: public NumberExpression<Integer> locate(String str, Expression<Integer> start) {
          return Expressions.numberOperation(Integer.class, Ops.StringOps.LOCATE2, ConstantImpl.create(str), mixin, start);
      }
docs: Create a {@code locate(str, this, start)} expression
  
  <p>Get the position of the given String in this String, the first position is 1</p>
  
  @param str string
  @param start start
  @return locate(str, this, start)