rem: hexToChar(char hi, char low) { return (hexToChar(hi) << 4)	| hexToChar(low);
add: hexToChar(char hex) { if ('0' <= hex && hex <= '9') return hex-'0'; else if ('a' <= hex && hex <= 'f') return hex-'a'+10; else if ('A' <= hex && hex <= 'F') return hex-'A'+10; else throw new Err(std::string("Sniffer parser error: invalid hex digit '") + hex + "' passed to hexToChar()", -1);
context: hexToChar(char hi, char low) {	return (hexToChar(hi) << 4)	| hexToChar(low);}