Return the decimal value of a hex character.

Synopsis

Defined in header <boost/url/grammar/hexdig_chars.hpp>

signed char
hexdig_value(
    char ch);

Description

This function returns the decimal value of a hexadecimal character, or -1 if the argument is not a valid hexadecimal digit.

BNF

HEXDIG      = DIGIT
            / "A" / "B" / "C" / "D" / "E" / "F"
            / "a" / "b" / "c" / "d" / "e" / "f"

Parameters

Return Value

The decimal value or -1

Convenience header <boost/url/grammar.hpp>