src/main/java/org/organicdesign/fp/collections/PersistentVector.java
static public <T> PersistentVector<T> ofIter(Iterable<T> items) {
        MutableVector<T> ret = emptyMutable();
        for (T item : items) {
            ret.append(item);
        }
        return ret.immutable();
    }
static public <T> PersistentVector<T> ofIter(Iterable<T> items) {
        MutableVector<T> ret = emptyMutable();
        for (T item : items) {
            ret.append(item);
        }
        return ret.immutable();
    }
Public static factory method to create a vector from an Iterable.  A varargs version of this
method is: {@link org.organicdesign.fp.StaticImports#vec(Object...)}.