original_string: public function edit_validate_field($usernew) {
          global $DB;
  
          $errors = array();
          // Get input value.
          if (isset($usernew->{$this->inputname})) {
              if (is_array($usernew->{$this->inputname}) && isset($usernew->{$this->inputname}['text'])) {
                  $value = $usernew->{$this->inputname}['text'];
              } else {
                  $value = $usernew->{$this->inputname};
              }
          } else {
              $value = '';
          }
  
          // Check for uniqueness of data if required.
          if ($this->is_unique() && (($value !== '') || $this->is_required())) {
              $data = $DB->get_records_sql('
                      SELECT id, userid
                        FROM {user_info_data}
                       WHERE fieldid = ?
                         AND ' . $DB->sql_compare_text('data', 255) . ' = ' . $DB->sql_compare_text('?', 255),
                      array($this->field->id, $value));
              if ($data) {
                  $existing = false;
                  foreach ($data as $v) {
                      if ($v->userid == $usernew->id) {
                          $existing = true;
                          break;
                      }
                  }
                  if (!$existing) {
                      $errors[$this->inputname] = get_string('valuealreadyused');
                  }
              }
          }
          return $errors;
      }
code: public function edit_validate_field($usernew) {
          global $DB;
  
          $errors = array();
          // Get input value.
          if (isset($usernew->{$this->inputname})) {
              if (is_array($usernew->{$this->inputname}) && isset($usernew->{$this->inputname}['text'])) {
                  $value = $usernew->{$this->inputname}['text'];
              } else {
                  $value = $usernew->{$this->inputname};
              }
          } else {
              $value = '';
          }
  
          // Check for uniqueness of data if required.
          if ($this->is_unique() && (($value !== '') || $this->is_required())) {
              $data = $DB->get_records_sql('
                      SELECT id, userid
                        FROM {user_info_data}
                       WHERE fieldid = ?
                         AND ' . $DB->sql_compare_text('data', 255) . ' = ' . $DB->sql_compare_text('?', 255),
                      array($this->field->id, $value));
              if ($data) {
                  $existing = false;
                  foreach ($data as $v) {
                      if ($v->userid == $usernew->id) {
                          $existing = true;
                          break;
                      }
                  }
                  if (!$existing) {
                      $errors[$this->inputname] = get_string('valuealreadyused');
                  }
              }
          }
          return $errors;
      }
code_tokens: public function edit_validate_field ( $ usernew ) { global $ DB ; $ errors = array ( ) ; // Get input value. if ( isset ( $ usernew -> { $ this -> inputname } ) ) { if ( is_array ( $ usernew -> { $ this -> inputname } ) && isset ( $ usernew -> { $ this -> inputname } [ 'text' ] ) ) { $ value = $ usernew -> { $ this -> inputname } [ 'text' ] ; } else { $ value = $ usernew -> { $ this -> inputname } ; } } else { $ value = '' ; } // Check for uniqueness of data if required. if ( $ this -> is_unique ( ) && ( ( $ value !== '' ) || $ this -> is_required ( ) ) ) { $ data = $ DB -> get_records_sql ( '
                      SELECT id, userid
                        FROM {user_info_data}
                       WHERE fieldid = ?
                         AND ' . $ DB -> sql_compare_text ( 'data' , 255 ) . ' = ' . $ DB -> sql_compare_text ( '?' , 255 ) , array ( $ this -> field -> id , $ value ) ) ; if ( $ data ) { $ existing = false ; foreach ( $ data as $ v ) { if ( $ v -> userid == $ usernew -> id ) { $ existing = true ; break ; } } if ( ! $ existing ) { $ errors [ $ this -> inputname ] = get_string ( 'valuealreadyused' ) ; } } } return $ errors ; }
docstring: Validate the form field from profile page
  
  @param stdClass $usernew
  @return  string  contains error message otherwise null
docstring_tokens: Validate the form field from profile page