The following table describes character matching syntax:
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 Matches any character except \n. When within a character class, the . will be treated as a period character.  | 
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 Matches any single character in the specified set of characters.  | 
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 Matches any single character not in the specified set of characters.  | 
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 Use of a hyphen (-) allows specification of contiguous character ranges.  | 
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 Matches any character in the Unicode general category specified by name (for example, Ll, Nd, Z). See the "B.3 Supported Unicode General Categories", for details on the Unicode general category.  | 
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 Matches any word character, which includes letters, digits, and underscores.  | 
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 Escaped built-in character classes such as \w and \s may be used in a character class. This example matches any period, word or whitespace character.  |