Why does my put work but the Phobos put doesn't work with a slice?

void main()
{
    import std.range : phobos_put = put;
  
    enum testLen = 4;
    auto a = new int[testLen];
    auto b = new int[testLen];

    auto slice = a[1..$-1];
    slice.phobos_put([2, 3]);
    //a[1..$-1].phobos_put([2, 3]);
    b[1..$-1].put([2, 3]);

    import std.conv : text;
    assert(a == b, text(a));
}

void put(R)(R[] range, R[] source)
{
  assert(source.length <= range.length);
  foreach(element; source)
  {
    range[0] = element;  // range.front()
    range = range[1..$]; // range popFront()
  }
}

SDB@79