lending-iterator 0.1.6-rc1

Fully general lending iterators in stable rust: windows_mut!
Documentation
<style>
@import url('https://fonts.cdnfonts.com/css/apercu');
@import url('https://fonts.cdnfonts.com/css/fira-code-2');

details.custom > summary {
    display: list-item;
    /* https://medium.com/simple-human/buttons-shouldnt-have-a-hand-cursor-b11e99ca374b */
    cursor: default;
}

.summary-box {
    display: inline-block;
}

details.custom > summary > .summary-box > span {
    visibility: hidden;
    position: relative;
}
details.custom > summary > .summary-box > span:after {
    content: "Click to show";
    visibility: visible;
    position: absolute;
    top: 0;
    left: 0;
}
details[open].custom > summary > .summary-box > span:after {
    content: "Click to hide";
    visibility: visible;
    position: absolute;
    top: 0;
    left: 0;
}

/**
 *  Button style from https://github.com/ubuwaits/css3-buttons
 *        MIT-Licensed under the name of Chad Mazzola
 *       rev: c5d2eccd18c0be21c291982e40da0c590f8bc32f
 *
 *  I made a few changes, the original is then commented out just above each.
 **/
.summary-box {
  background-color: #eeeeee;
  background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #eeeeee), color-stop(100%, #cccccc));
  background-image: -webkit-linear-gradient(top, #eeeeee, #cccccc);
  background-image: -moz-linear-gradient(top, #eeeeee, #cccccc);
  background-image: -ms-linear-gradient(top, #eeeeee, #cccccc);
  background-image: -o-linear-gradient(top, #eeeeee, #cccccc);
  background-image: linear-gradient(top, #eeeeee, #cccccc);
  border: 1px solid #ccc;
  border-bottom: 1px solid #bbb;
  border-radius: 3px;
  color: #333;
  /* font: bold 11px/1 "Lucida Grande", "Lucida Sans Unicode", "Lucida Sans", Geneva, Verdana, sans-serif; */
  font: bold 11px/1 "Fira Code", "Apercu Mono", "Courier New", sans-serif;
  /* padding: 8px 0; */
  padding-top: 2px;
  text-align: center;
  text-shadow: 0 1px 0 #eee;
  /* width: 150px; */
}
.summary-box:hover {
    background-color: #dddddd;
    background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #dddddd), color-stop(100%, #bbbbbb));
    background-image: -webkit-linear-gradient(top, #dddddd, #bbbbbb);
    background-image: -moz-linear-gradient(top, #dddddd, #bbbbbb);
    background-image: -ms-linear-gradient(top, #dddddd, #bbbbbb);
    background-image: -o-linear-gradient(top, #dddddd, #bbbbbb);
    background-image: linear-gradient(top, #dddddd, #bbbbbb);
    border: 1px solid #bbb;
    border-bottom: 1px solid #999;
    /* cursor: pointer; */
    text-shadow: 0 1px 0 #ddd;
}
.summary-box:active {
    border: 1px solid #aaa;
    border-bottom: 1px solid #888;
    -webkit-box-shadow: inset 0 0 5px 2px #aaaaaa, 0 1px 0 0 #eeeeee;
    box-shadow: inset 0 0 5px 2px #aaaaaa, 0 1px 0 0 #eeeeee;
}
</style>