public static Set<XPathExpression> collectMatchingExpressions(XPathExpression expression) {
        final PsiElement usageBlock = XsltCodeInsightUtil.getUsageBlock(expression);
        if (usageBlock == null) return Collections.emptySet();

        final ExpressionCollector visitor = new ExpressionCollector(expression);
        usageBlock.accept(visitor);

        return visitor.getMatches();
    }
public static Set<XPathExpression> collectMatchingExpressions(XPathExpression expression)