clear_spell_chartab(spelltab_T *sp)
{
    int		i;

    // Init everything to FALSE (zero).
    CLEAR_FIELD(sp->st_isw);
    CLEAR_FIELD(sp->st_isu);
    for (i = 0; i < 256; ++i)
    {
	sp->st_fold[i] = i;
	sp->st_upper[i] = i;
    }

    // We include digits.  A word shouldn't start with a digit, but handling
    // that is done separately.
    for (i = '0'; i <= '9'; ++i)
	sp->st_isw[i] = TRUE;
    for (i = 'A'; i <= 'Z'; ++i)
    {
	sp->st_isw[i] = TRUE;
	sp->st_isu[i] = TRUE;
	sp->st_fold[i] = i + 0x20;
    }
    for (i = 'a'; i <= 'z'; ++i)
    {
	sp->st_isw[i] = TRUE;
	sp->st_upper[i] = i - 0x20;
    }
}
Unknown