original_string: public function sql_isnotempty($tablename, $fieldname, $nullablefield, $textfield) {
          return ' ( NOT ' . $this->sql_isempty($tablename, $fieldname, $nullablefield, $textfield) . ') ';
      }
code: public function sql_isnotempty($tablename, $fieldname, $nullablefield, $textfield) {
          return ' ( NOT ' . $this->sql_isempty($tablename, $fieldname, $nullablefield, $textfield) . ') ';
      }
code_tokens: public function sql_isnotempty ( $ tablename , $ fieldname , $ nullablefield , $ textfield ) { return ' ( NOT ' . $ this -> sql_isempty ( $ tablename , $ fieldname , $ nullablefield , $ textfield ) . ') ' ; }
docstring: Returns the proper SQL to know if one field is not empty.
  
  Note that the function behavior strongly relies on the
  parameters passed describing the field so, please,  be accurate
  when specifying them.
  
  This function should be applied in all the places where conditions of
  the type:
  
  ... AND fieldname != '';
  
  are being used. Final result for text fields should be:
  
  ... AND ' . sql_isnotempty('tablename', 'fieldname', true/false, true/false);
  
  and for varchar fields result should be:
  
  ... AND fieldname != :empty; "; $params['empty'] = '';
  
  (see parameters description below)
  
  @param string $tablename Name of the table (without prefix). This is not used for now but can be
  necessary in the future if we want to use some introspection using
  meta information against the DB.
  @param string $fieldname The name of the field we are going to check.
  @param bool $nullablefield Specifies if the field is nullable (true) or not (false) in the DB.
  @param bool $textfield Specifies if it is a text (also called clob) field (true) or a varchar one (false).
  @return string The sql code to be added to check for non empty values.
docstring_tokens: Returns the proper SQL to know if one field is not empty .