STATIC char *
S_scan_word(pTHX_ register char *s, char *dest, STRLEN destlen, int allow_package, STRLEN *slp)
{
register char *d = dest;
register char * const e = d + destlen - 3; /* two-character token, ending NUL */
for (;;) {
if (d >= e)
Perl_croak(aTHX_ ident_too_long);
if (isALNUM(*s)) /* UTF handled below */
*d++ = *s++;
else if (*s == '\'' && allow_package && isIDFIRST_lazy_if(s+1,UTF)) {
*d++ = ':';
*d++ = ':';
s++;
}
else if (*s == ':' && s[1] == ':' && allow_package && s[2] != '$') {
*d++ = *s++;
*d++ = *s++;
}
else if (UTF && UTF8_IS_START(*s) && isALNUM_utf8((U8*)s)) {
char *t = s + UTF8SKIP(s);
while (UTF8_IS_CONTINUED(*t) && _is_utf8_mark((U8*)t))
t += UTF8SKIP(t);
if (d + (t - s) > e)
Perl_croak(aTHX_ ident_too_long);
Copy(s, d, t - s, char);
d += t - s;
s = t;
}
else {
bool
Perl_is_utf8_mark(pTHX_ const U8 *p)
{
PERL_ARGS_ASSERT_IS_UTF8_MARK;
return _is_utf8_mark(p);
}