libtld/tld_emails.cpp
bool is_atom_char(char c)
{
    return (c >= 'A' && c <= 'Z')
        || (c >= 'a' && c <= 'z')
        || (c >= '0' && c <= '9')
        || c == '!' || c == '#'
        || c == '$' || c == '%'
        || c == '&' || c == '\''
        || c == '*' || c == '+'
        || c == '-' || c == '/'
        || c == '=' || c == '?'
        || c == '^' || c == '_'
        || c == '`' || c == '{'
        || c == '|' || c == '}'
        || c == '~';
}
/** \brief Check whether the character is a valid atom character.
 *
 * Characters that are valid atom characters can appear as is in
 * a display name. Other characters need to be quoted. This function
 * check whether a character is an atom character or not.
 *
 * \param[in] c  The character to be checked.
 *
 * \return true if the \p c character is an atom character.
 */
\brief Check whether the character is a valid atom character.
Characters that are valid atom characters can appear as is in
a display name. Other characters need to be quoted. This function
check whether a character is an atom character or not.

\param[in] c  The character to be checked.

\return true if the \p c character is an atom character.
\ brief Check whether the character is a valid atom character . Characters that are valid atom characters can appear as is in a display name . Other characters need to be quoted . This function check whether a character is an atom character or not . \ param [ in ] c The character to be checked . \ return true if the \ p c character is an atom character .
bool is_atom_char(char c)
{
    return (c >= 'A' && c <= 'Z')
        || (c >= 'a' && c <= 'z')
        || (c >= '0' && c <= '9')
        || c == '!' || c == '#'
        || c == '$' || c == '%'
        || c == '&' || c == '\''
        || c == '*' || c == '+'
        || c == '-' || c == '/'
        || c == '=' || c == '?'
        || c == '^' || c == '_'
        || c == '`' || c == '{'
        || c == '|' || c == '}'
        || c == '~';
}
bool is_atom_char ( char c ) { return ( c >= ' ' && c <= ' ' ) || ( c >= ' ' && c <= ' ' ) || ( c >= ' ' && c <= ' ' ) || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' \' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' || c == ' ' ; }
\brief Check whether the character is a valid atom character.
\ brief Check whether the character is a valid atom character .