How to define and reference an array of CONSTANTS in deployed module

@Wilberforce the constructor function isn't actually required as exports is normally just an object (but for most modules you would have one anyway so your method makes a lot of sense).

The first bit of @Robin's code is a valid module:

var C = {
  U : "up",
  D : "down",
  L : "left",
  R : "right",
  N : "north",
  E : "east",
  S : "south",
  W : "west",
  T : "top",
  M : "middle",
  B : "bottom"
};
exports = C;

I'm not sure I understand the question @Robin but I think you're asking if you can reference one module from another one? Yes, you can.

Assume you have the code above in one module https://github.com/.../C.js. The next module can be:

var C = require("https://github.com/.../C.js");
var GROUPS = {
  COMPASS   : [{N:C.N}, {E:C.E}, {S:C.S}, {W:C.W}],
//  COMPASS   : [ C.N, C.E, C.S, C.W ],  
  DIRECTION : [ C.U, C.D, C.L, C.R ],
  VERTICAL  : [ C.T, C.M, C.B ]
};
exports = GROUPS;

Then you can access both:

var C = require("https://github.com/.../C.js");
var GROUPS = require("https://github.com/.../GROUPS.js");
print( C.S );
print( GROUPS.COMPASS );
print( GROUPS.COMPASS.E );

OR: Maybe you just want both in one module? That's easy too:

var exports={}; // you don't need this in the module itself. It's just when in the IDE
var C = {
  U : "up",
  D : "down",
  L : "left",
  R : "right",
  N : "north",
  E : "east",
  S : "south",
  W : "west",
  T : "top",
  M : "middle",
  B : "bottom"
};
exports.C = C; //<------------------------------- Note the added '.C'
var GROUPS = {
  COMPASS   : [{N:C.N}, {E:C.E}, {S:C.S}, {W:C.W}],
//  COMPASS   : [ C.N, C.E, C.S, C.W ],  
  DIRECTION : [ C.U, C.D, C.L, C.R ],
  VERTICAL  : [ C.T, C.M, C.B ]
};
exports.GROUPS = GROUPS; //<------------------------------- Note the added '.GROUPS'

Now you can use it like:

var module = require(" ... ");
print( module.C.S );
print( module.GROUPS.COMPASS );
print( module.GROUPS.COMPASS.E );

or

var module = require(" ... ");
var C = module.C;
var GROUPS = module.GROUPS;
print( C.S );
print( GROUPS.COMPASS );
print( GROUPS.COMPASS.E );