Check is value valid.

@param string $value
@return bool
423878
public function isValueValid($value) {
		return $value instanceof Type\PlaceType || $value instanceof Type\PostalAddressType || $value instanceof DataType\TextType;
	}
634797
public function isValueValid($value) {
		return $value instanceof Type\DistanceType || $value instanceof DataType\NumberType || $value instanceof DataType\TextType;
	}
570722
public function isValid($value)
    {
        foreach ((array) $value as $val) {
            if (\MUtil_String::contains($val, $this->_options[0])) {
                return true;
            }
        }
        return false;
    }
851213
public function isValid($value)
    {
        $result = preg_match('/(.+)/i', $value);
        if (!$result) {
            $this->addMessage('notEmpty');
        }
        return (boolean) $result;
    }
855694
public function isValid($value)
    {
        foreach ($this as $type) {
            if ($type->isValid($value)) {
                return true;
            }
        }

        return false;
    }
10375
protected function checkValidity($value) : bool
    {
        if (preg_match(static::$regex, $value)) {
            return true;
        } elseif ('' === $value) {
            return true;
        } else {
            return false;
        }
    }
655628
protected function checkValidity($value) : bool
    {
        if ('' === $value) {
            return true;
        }
        $date = date_create($value);
        if (false === $date) {
            return false;
        }
        return true;
    }
1060467
public function isValueValid($value) {
		return $value instanceof Type\ListItemType || $value instanceof DataType\TextType || $value instanceof Type\ThingType;
	}
527291
public function isValid($value) : bool
    {
        if ($value === null && $this->nullable) {
            return true;
        }

        return $value instanceof \DateTimeImmutable;
    }
233555
public function isValid($value) : bool
    {
        if ($value === null && $this->nullable) {
            return true;
        }

        return is_array($value);
    }
31424
public function isValid($value)
    {
        $this->_setValue($value);

        if (!is_string($value)) {
            return false;
        }

        return Zend_Uri::check($value);
    }
1280346
public function isValueValid($value) {
		return $value instanceof Type\ProductType || $value instanceof DataType\TextType || $value instanceof DataType\URLType;
	}
121216
public static function isValid($value)
    {
        if (!is_string($value)) {
            return false;
        }

        $type = self::getType($value);

        return !($type === null);
    }
1000801
public function isValueValid($value) {
		return $value instanceof Type\Distance || $value instanceof DataType\NumberType || $value instanceof DataType\TextType;
	}
450467
public function isValueValid($value) {
		return $value instanceof Type\QualitativeValueType || $value instanceof DataType\TextType || $value instanceof DataType\URLType;
	}
111836
public function isValueValid($value) {
		return $value instanceof Type\Place || $value instanceof Type\PostalAddress || $value instanceof DataType\TextType;
	}
879189
public function validateValue($value)
    {
        // make sure string length is limited to avoid DOS attacks
        $valid = is_string($value) && strlen($value) <= 254 && (preg_match($this->pattern, $value) || $this->allowName && preg_match($this->fullPattern, $value));
        return $valid;
    }