code: public static BooleanIsEqual isEqual(ComparableExpression<Boolean> left, Boolean constant) {
          return new BooleanIsEqual(left, constant(constant));
      }
docs: Creates a BooleanIsEqual expression from the given expression and constant.
  
  @param left  The left expression.
  @param constant The constant to compare to.
  @return A new BooleanIsEqual binary expression.