Returns values as a string.
@param mixed $value
@return string
480250
public function displayValue($value): string
    {
        if ($value === null) {
            return 'NULL';
        }

        if ($value === true) {
            return 'TRUE';
        }

        if ($value === false) {
            return 'FALSE';
        }

        if (is_array($value)) {
            return Json::encode($value);
        }

        return '"' . str_replace('"', '\"', $value) . '"';
    }
771086
public function string($value)
    {
        if ($this->notBeEmpty($value)) {
            if (is_string($value) && preg_match('/[A-Za-z]+/i', $value)) {
                return true;
            } else {
                return false;
            }
        } else {
            return false;
        }
    }
1143349
public static function stringify($value)
    {
        if (is_string($value)) {
            return $value;
        }
        if ($value === null || is_bool($value)) {
            return var_export($value, true);
        }

        if (is_array($value) || (is_object($value) && !method_exists($value, '__toString'))) {
            return json_encode($value, JSON_ERROR_NONE | JSON_UNESCAPED_SLASHES);
        }
        return (string)$value;
    }
800771
public function parseString($value) {
    if (is_string($value)) {
      return $value;
    }

    $exportValue = var_export($value, true);
    throw new ParseException("'$exportValue' can not be parsed as a string");
  }
907470
public static function factory($value): string
    {
        $data = Data::make($value);
        return self::evaluate($data, $value)->isString()->getValue();
    }
1372316
protected static function convertString($value)
    {
        if (strpos($value, '\\') === false) {
            return $value;
        }

        return preg_replace_callback(
            '/\\\(n|r|t|v|e|f|"|\\\)/',
            function ($match) {
                switch ($match[1][0]) {
                    case 'n':
                        return "\n";
                    case 'r':
                        return "\r";
                    case 't':
                        return "\t";
                    case 'v':
                        return "\v";
                    case 'e':
                        return "\e";
                    case 'f':
                        return "\f";
                    case '"':
                        return '"';
                    case '\\':
                        return '\\';
                }
            },
            $value
        );
    }
570158
public function stringify($value): string
    {
        if ($value instanceof \DateTimeInterface) {
            return $value->format('Y-m-d');
        }

        if (is_array($value)) {
            return self::ARRAY_VALUE;
        }

        if (is_object($value) && !method_exists($value, '__tostring')) {
            return self::OBJECT_VALUE;
        }

        return (string)$value;
    }
1128373
public static function stringify($value)
    {
        $string = '';
        if (is_scalar($value)) {
            // integer, float, string, boolean
            $string = (string)$value;
        } elseif (is_resource($value)) {
            // resource
            $string = '[resource]';
        } else {
            // array, object, null, callable
            $string = json_encode($value);
        }
        return $string;
    }
451762
public function getString($value) {
		if ($this->startsWith($value, '\'') && $this->endsWith($value, '\'')) {
			return ltrim(rtrim($value, '\''), '\'');
		}
		if ($this->startsWith($value, '"') && $this->endsWith($value, '"')) {
			return ltrim(rtrim($value, '"'), '"');
		}

		return $value;
	}
29701
static private function stringify($value)
        {
            if (is_bool($value)) {
                return $value ? '<TRUE>' : '<FALSE>';
            }

            if (is_scalar($value)) {
                $val = (string) $value;

                if (strlen($val) > 100) {
                    $val = substr($val, 0, 97) . '...';
                }

                return $val;
            }

            if (Arrays::is($value)) {
                return '<ARRAY>';
            }

            if (is_object($value)) {
                return get_class($value);
            }

            if (is_resource($value)) {
                return '<RESOURCE>';
            }

            if ($value === null) {
                return '<NULL>';
            }

            return 'unknown';
        }
201235
public static function toString(Value $value)
    {
        if ($value instanceof BooleanValue) {
            return $value->getValue() ? 'true' : 'false';
        } elseif ($value instanceof NumberValue || $value instanceof TextValue) {
            return strval($value->getValue());
        } elseif ($value instanceof DateTimeValue) {
            return $value->getValue() !== null
                ? AdManagerDateTimes::toDateTimeString($value->getValue()) : '';
        } elseif ($value instanceof DateValue) {
            return AdManagerDates::toDateString($value->getValue());
        } elseif ($value instanceof SetValue) {
            $pqlValues = $value->getValues();
            if ($pqlValues !== null) {
                $valuesAsStrings = [];
                foreach ($pqlValues as $pqlValue) {
                    $valuesAsStrings[] = self::toString($pqlValue);
                }

                return implode(',', $valuesAsStrings);
            } else {
                return '';
            }
        } else {
            throw new InvalidArgumentException(
                sprintf('Unsupported value type [%s]', get_class($value))
            );
        }
    }
120865
protected function serializeValue($value)
    {
        if (is_string($value)) {
            return $value;
        }
        if (is_object($value) || is_array($value)) {
            return json_encode($value);
        }
    }
1053917
public static function convertString($value)
    {
        if (\strpos($value, '\\') === false) {
            return \substr($value, 1, -1);
        }

        if ($value[0] === "'") {
            return \strtr(\substr($value, 1, -1), ['\\\\' => '\\', '\\\'' => '\'']);
        }

        $value = \substr($value, 1, -1);

        return \preg_replace_callback(
            '/\\\(n|r|t|v|e|f|\$|"|\\\|x[0-9A-Fa-f]{1,2}|u{[0-9a-f]{1,6}}|[0-7]{1,3})/',
            function ($match) {
                switch ($match[1][0]) {
                    case 'n':
                        return "\n";
                    case 'r':
                        return "\r";
                    case 't':
                        return "\t";
                    case 'v':
                        return "\v";
                    case 'e':
                        return "\e";
                    case 'f':
                        return "\f";
                    case '$':
                        return '$';
                    case '"':
                        return '"';
                    case '\\':
                        return '\\';
                    case 'x':
                        return \chr(\hexdec(\substr($match[0], 1)));
                    case 'u':
                        return Strings::chr(\hexdec(\substr($match[0], 1)));
                    default:
                        return \chr(\octdec($match[0]));
                }
            },
            $value
        );
    }
400418
private function as_string( $value ) {

		if ( is_object( $value ) && method_exists( $value, '__toString' ) ) {
			$value = (string) $value;
		}

		if ( is_string( $value ) ) {
			return $value;
		} elseif ( is_null( $value ) ) {
			return 'NULL';
		} elseif ( is_bool( $value ) ) {
			return $value ? '(boolean) TRUE' : '(boolean) FALSE';
		}

		if ( is_object( $value ) ) {
			$value = get_class( $value );
			$type  = '(object) ';
		} elseif ( is_array( $value ) ) {
			$type  = '';
			$value = var_export( $value, TRUE );
		}

		isset( $type ) or $type = '(' . gettype( $value ) . ') ';

		return $type . (string) $value;
	}
202297
public function transform($value)
    {
        if (null === $value || !($value instanceof Collection)) {
            return '';
        }

        $string = '';
        foreach ($value as $item) {
            $string .= $item->getId();

            if ($value->last() != $item) {
                $string .= ',';
            }
        }

        return $string;
    }
353889
protected static function stringify($value): string
    {
        if (is_object($value)) {
            return 'Object(' . get_class($value) . ')';

        } elseif (is_array($value)) {
            $strings = [];
            foreach ($value as $k => $v) {
                $strings[] = sprintf('%s => %s', $k, self::stringify($v));
            }
            return 'Array(' . implode(', ', $strings) . ')';

        } elseif (is_resource($value)) {
            return 'Resource (' . get_resource_type($value) . ')';

        } elseif (is_null($value)) {
            return 'null';

        } elseif (is_bool($value)) {
            return $value ? 'true' : 'false';
        }

        return "'" . (string)$value . "'";
    }
345162
protected function serializeValue($value)
    {
        $serialized = var_export($value, true);
        if ($serialized === 'NULL') {
            $serialized = strtolower($serialized);
        }

        return $serialized;
    }