Count Childrens in a TYPOSCRIPT menu - typo3

Question

i am wondering if there is a way in TYPOSCRIPT to count the childrens in a menu.
The output should be something like:
<ul class="ebene1" data-elements="4">
<li>Element 1</li>
<li>Element 2</li>
<li>Element 2</li>
<li>Element 2</li>
</ul>
My Code looks like this:
script.NAV = HMENU
script.NAV {
special = directory
special.value = 6
1 = TMENU
1 {
expAll = 1
noBlur = 1
wrap = <ul class="menu main" id="nav-main">|</ul>
NO = 1
NO.wrapItemAndSub = <li class="first element1">|</li> |*| <li class="element1">|</li> |*| <li class="last element1">|</li>
CUR = 1
CUR.wrapItemAndSub = <li class="first element1 current">|</li> |*| <li class="element1 current">|</li> |*| <li class="last element1 current">|</li>
...
Thanks, any help is really appreciated.

Answer 1

Use the register {register:count_MENUOBJ} like this should solve your problem.
1 = TMENU
1 {
NO = 1
NO {
wrapItemAndSub.insertData = 1
wrapItemAndSub = <li class="element-{register:count_MENUOBJ}">|</li>
}
}

Answer 2

Actually although that may be done as #Marcus showed (I believe that snippet works, didn't check) it is probably faster approach to us JavaScript for this; as easy as:
<ul class="ebene1">
<li>Element 1</li>
<li>Element 2</li>
<li>Element 3</li>
<li>Element X</li>
</ul>
<script>$('.ebene1').attr('data-elements', $('.menu > li').length);</script>
And CSS like:
.ebene1[data-elements="4"] {
background-color: yellow;
}
On the other hand...
If you have dynamic menu with unknown number of items, instead adding many CSS declarations like,
.ebene1[data-elements="3"] li {width: 33.333%;}
.ebene1[data-elements="4"] li {width: 25%;}
.ebene1[data-elements="5"] li {width: 20%;}
Avoid adding the data- attribute via JS and just change the width by calculating the correct value:
$('.ebene1 > li').css({width: 100 / $('.ebene1 > li').length + '%'});

Answer 3

You need the stdWrap function numrows. There you can add any table together with a select statement. Here is an example:
lib.countmenu = COA
lib.countmenu {
10 = HMENU
10.1 = TMENU
10.1 {
wrap = <ul>|</ul>
NO {
stdWrap.cObject = COA
stdWrap.cObject {
30 = TEXT
30.numRows.table = pages
30.numRows.select.pidInList.field = uid
30.numRows.select.where = nav_hide!=1 AND doktype!=5 AND doktype!=6
30.dataWrap = {field:title} [|]
}
wrapItemAndSub = <li>|</li>
}
}
}