StringCases::meta
StringFreeQ::meta
StringSplit::meta
StringReplaceList::meta
StringPosition::meta
StringReplace::meta
An error occurs because a string containing a single character is not a valid value for the MetaCharacters option:
StringPosition["1234568", "3xx", MetaCharacters -> "x"]This shows a valid value for the MetaCharacters option:
StringPosition["1234568", "3xx", MetaCharacters -> {"\\", "x", "*"}]