demo/typescript.js
function findEnclosingNode(range, sourceFile) {
            return find(sourceFile);
            function find(n) {
                var candidate = ts.forEachChild(n, function (c) { return ts.startEndContainsRange(c.getStart(sourceFile), c.end, range) && c; });
                if (candidate) {
                    var result = find(candidate);
                    if (result) {
                        return result;
                    }
                }
                return n;
            }
        }
function findEnclosingNode(range, sourceFile) {
            return find(sourceFile);
            function find(n) {
                var candidate = ts.forEachChild(n, function (c) { return ts.startEndContainsRange(c.getStart(sourceFile), c.end, range) && c; });
                if (candidate) {
                    var result = find(candidate);
                    if (result) {
                        return result;
                    }
                }
                return n;
            }
        }
find node that fully contains given text range