type ENT_OPTION_STRING = 'ENT_NOQUOTES' | 'ENT_HTML_QUOTE_SINGLE' | 'ENT_HTML_QUOTE_DOUBLE' | 'ENT_COMPAT' | 'ENT_QUOTES' | 'ENT_IGNORE';
type ENT_OPTION_NUMBER = 0 | 1 | 2 | 3 | 4;
type ENT_OPTION = ENT_OPTION_STRING | ENT_OPTION_NUMBER;
declare const HTMLSPECIALCHARS_ENT_NOQUOTES: ENT_OPTION_STRING;
declare const HTMLSPECIALCHARS_ENT_HTML_QUOTE_SINGLE: ENT_OPTION_STRING;
declare const HTMLSPECIALCHARS_ENT_HTML_QUOTE_DOUBLE: ENT_OPTION_STRING;
declare const HTMLSPECIALCHARS_ENT_COMPAT: ENT_OPTION_STRING;
declare const HTMLSPECIALCHARS_ENT_QUOTES: ENT_OPTION_STRING;
declare const HTMLSPECIALCHARS_ENT_IGNORE: ENT_OPTION_STRING;
declare function htmlspecialchars(string: string, quoteStyle?: ENT_OPTION | ENT_OPTION[], charset?: null, doubleEncode?: boolean): string;

declare function md5(string: string): any;

declare function serialize(mixedValue: any): string;

declare function unserialize(string: string, showError?: boolean): any;

declare function utf8Decode(string: string): string;

declare function utf8Encode(string: string): string;

export { type ENT_OPTION, HTMLSPECIALCHARS_ENT_COMPAT, HTMLSPECIALCHARS_ENT_HTML_QUOTE_DOUBLE, HTMLSPECIALCHARS_ENT_HTML_QUOTE_SINGLE, HTMLSPECIALCHARS_ENT_IGNORE, HTMLSPECIALCHARS_ENT_NOQUOTES, HTMLSPECIALCHARS_ENT_QUOTES, htmlspecialchars, md5, serialize, unserialize, utf8Decode, utf8Encode };