Locate the next token. Returns the token if found, null
otherwise. Null indicates an end of stream condition. To
sweep a conduit for lines using method next():
auto lines = new Lines!(char) (new File("myfile"));
while (lines.next)
Cout (lines.get).newline;
Alternatively, we can extract one line from a conduit:
auto line = (new Lines!(char) (new File("myfile"))).next;
The difference between next() and foreach() is that the
latter processes all tokens in one go, whereas the former
processes in a piecemeal fashion. To wit:
foreach (line; new Lines!(char) (new File("myfile")))
Cout(line).newline;