How to compute the cubehelix color scheme in Less.js?

I want to compute the cubehelix color scheme in Less so I can tweak some variables. I believe this necessitates CIE L*a*b color system. I ran across Chroma.js which seems like it would work for computing colors, but now I'd like to integrate this into Less.

Mike Bostock has implemented and extended cubehelix in JavaScript as a plugin for the D3.js visualisation library (see examples).

You can use the code of Bostock's plugin to write a custom function for Less.

1. Download and unzip the source from github at: https://github.com/less/less.js/archive/master.zip
2. Run npm install

3. Create a file called lib/less/functions/cubehelix.js and write down the following content into it:

   var Color = require("../tree/color"),
   functionRegistry = require("./function-registry");
   
   function d3_interpolate(y) {
   return function(a, b) {
         a = a.toHSL();
         b = b.toHSL();
         var radians = Math.PI / 180;
         var ah = (a.h + 120) * radians,
             bh = (b.h + 120) * radians - ah,
             as = a.s,
             bs = b.s - as,
             al = a.l,
             bl = b.l - al;
   
         if (isNaN(bs)) bs = 0, as = isNaN(as) ? b.s : as;
         if (isNaN(bh)) bh = 0, ah = isNaN(ah) ? b.h : ah;
   
         return function(t) {
           var h = ah + bh * t,
               l = Math.pow(al + bl * t, y),
               a = (as + bs * t) * l * (1 - l),
               cosh = Math.cos(h),
               sinh = Math.sin(h);
           return "#"
               + hex(l + a * (-0.14861 * cosh + 1.78277 * sinh))
               + hex(l + a * (-0.29227 * cosh - 0.90649 * sinh))
               + hex(l + a * (+1.97294 * cosh));
         };
       };
     }
   
   function hex(v) {
       var s = (v = v <= 0 ? 0 : v >= 1 ? 255 : v * 255 | 0).toString(16);
       return v < 0x10 ? "0" + s : s;
   }
   
   functionRegistry.addMultiple({
   cubehelix: function(y,a,b,t) {
   return new Color(d3_interpolate(y.value)(a,b)(t.value).slice(1),1);
   }   
   });
   

4. Open the lib/less/function/index.js file and append require("./cubehelix"); to the list of register functions, just before return functions;

5. Run grunt dist (to create a new version of less.js)

Now the following Less code:

p{color: cubehelix(1,red,blue,1);}
p{color: cubehelix(1,red,blue,0.5);}
p{color: cubehelix(1, hsl(300,50%,0%), hsl(-240,50%,100%), 0.3);}

outputs:

p {
  color: #766cfd;
}
p {
  color: #21ba40;
}
p {
  color: #4c4c4c;
}