bool advanceCharacter(Decoder& it)
{
char32_t ch;
if (!it.next(ch))
return false;
auto prevIt = it.getLogicalBegin();
if (Decoder::isForward)
{
while (it.next(ch))
{
if (!Unicode::isMark(ch))
{
it.setLogicalBegin(prevIt);
break;
}
prevIt = it.getLogicalBegin();
}
}
else
{
while (Unicode::isMark(ch) && it.next(ch))
{}
}
return true;
}
Decoder nextToken(Decoder& str, UnaryPredicate predicate)
{
auto token = str;
token.setLogicalEnd(str.getLogicalBegin());
char32_t ch;
while (str.next(ch) && !predicate(ch))
token.setLogicalEnd(str.getLogicalBegin());
return token;
}
Decoder nextNewline(Decoder& str)
{
auto newline = str;
char32_t ch;
while (str.next(ch))
{
switch (ch)
{
case '\n':
if (!Decoder::isForward)
{
auto copyOfStr = str;
if (str.next(ch) && ch != '\r')
str.setLogicalBegin(copyOfStr.getLogicalBegin());
}
newline.setLogicalEnd(str.getLogicalBegin());
return newline;
case '\v':
case '\f':
case Unicode::NEXT_LINE:
case Unicode::LINE_SEPARATOR:
case Unicode::PARAGRAPH_SEPARATOR:
newline.setLogicalEnd(str.getLogicalBegin());
return newline;
case '\r':
if (Decoder::isForward)
{
auto copyOfStr = str;
if (str.next(ch) && ch != '\n')
str.setLogicalBegin(copyOfStr.getLogicalBegin());
}
newline.setLogicalEnd(str.getLogicalBegin());
return newline;
default:
break;
}
newline.setLogicalBegin(str.getLogicalBegin());
}
return str;
}