chunking an array in jade template

Question

I have an array, and a mixin that takes an array as a param. How would I chunk the array into sections of four and pass to the mixin?

So something sort of like this but better and working:

 each index, i in myArray
     if i%4 == 0
         +carouselItem([myArray[i], myArray[i+1], myArray[i+2], myArray[i+3]])

Answer 1

I would suggest a bit different approach: convert your array into two-dimensional array in your request handler function and then perform iteration over two-dimensional array (array of arrays) in your Jade template.

With that approach the template will be much simpler and all conversion will happen inside the handler method (controller) where you can have access to different libraries etc.

Example: In order to convert an array into two-dimensional array you could use following method:

function arrayTo2DArray (list, howMany) {
    var result = []; input = list.slice(0); 
    while(a[0]) { 
        result.push(a.splice(0, howMany)); 
    }
    return result;
}

And your request handler could look as follows:

exports.handler = function(req, res) {

    // myArray with some values

    res.render('template' { 
        myArray: arrayTo2DArray(myArray, 4) 
    }
}

If your myArray was, say, ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'], arrayTo2DArray(myArray, 4) would return

[
    ['a', 'b', 'c', 'd'], 
    ['e', 'f', 'g', 'h']
]

Your Jade template could look like this (much simpler)

each values in myArray
    +carouselItem(values)

I hope that will help.