/**
* may be called by a callback to retrieve see <a
* href="doc-files/resyntax.html#rse">submatches</a>. Retrieving submatches must be done before
* the match is changed in any way. A typical call within an {@link FaAction} looks like
*
* <pre>
* public void invoke(StringBuilder out, int start, DfaRun r)
* throws CallbackException {
* {
* TextStore ts = r.submatches(out, start);
* ...
* }</pre>
*
* Parameter <code>txt</code> is not changed in any way.
*
* @param txt must contain the full match starting at position <code>start</code>. It may contain
* more characters.
* @param start is the position where the full match starts within <code>txt</code>
* @return a <code>TextStore</code> that contains the whole match as part 0 and submatches as
* subsequent parts. The return value is private to <code>this</code> and its contents may
* only be used locally in a callback. After returning from the callback, the contents of the
* result may soon change.
*/
public TextStore submatches(StringBuilder txt, int start) {
readTs.clear();
// System.out.println("-->"+txt+"<--, `"+txt.substring(start)
// +"' "+smd.size);
readTs.appendPart(txt, start, txt.length());
smd.analyze(readTs, action);
return readTs;
}
/**
* returns a <code>TextStore</code> which contains submatches, if any, pertaining to the most
* recent match. The object returned should be treated read-only. Its contents are only valid
* until the next match operation.
*
* @throws IllegalStateException if the most recent application of <code>this</code> did not yield
* a match.
*/
public TextStore submatches() {
if (a == null || a == DfaRun.EOF) {
throw new IllegalStateException("no recent match available");
}
if (!analyzed) {
analyzed = true;
ts.clear();
ts.appendPart(out, 0, out.length());
smd.analyze(ts, a);
}
return ts;
}