Return the index into the stream of the input symbol referred to by {@code LA(1)}.
<p>The behavior of this method is unspecified if no call to an {@link IntStream initializing method} has occurred after this stream was constructed.</p>
See Implementation
Return the index into the stream of the input symbol referred to by {@code LA(1)}.
<p>The behavior of this method is unspecified if no call to an {@link IntStream initializing method} has occurred after this stream was constructed.</p>