@uml
Return an {@link Interval} indicating the index in the
{@link TokenStream} of the first and last token associated with this
subtree. If this node is a leaf, then the interval represents a single
token and has interval i..i for token index i.
<p>An interval of i..i-1 indicates an empty interval at position
i in the input stream, where 0 <= i <= the size of the input
token stream. Currently, the code base can only have i=0..n-1 but
in concept one could have an empty interval after EOF. </p>
<p>If source interval is unknown, this returns {@link Interval#INVALID}.</p>
<p>As a weird special case, the source interval for rules matched after
EOF is unspecified.</p>
@uml Return an {@link Interval} indicating the index in the {@link TokenStream} of the first and last token associated with this subtree. If this node is a leaf, then the interval represents a single token and has interval i..i for token index i.
<p>An interval of i..i-1 indicates an empty interval at position i in the input stream, where 0 <= i <= the size of the input token stream. Currently, the code base can only have i=0..n-1 but in concept one could have an empty interval after EOF. </p>
<p>If source interval is unknown, this returns {@link Interval#INVALID}.</p>
<p>As a weird special case, the source interval for rules matched after EOF is unspecified.</p>