Arabic to Greek numeral converter, 1 - 10

One of the things that's straight-forward in JavaScript is Unicode support. If you want to return ϝ (lowercase digamma, not a simple f), you simply tell it to do so. No look-up, conversion or unreadable Unicode codes required.

I want to build a translator between Arabic and Greek numerals. Since my projects tend to take forever to complete, I decided to post what I have instead of waiting till it's finished. The code currently supports 1 - 10 and translates them to the Unicode Greek equivalent.

I wrote it the most straight-forward way I could think of. It's not necessarily the best way.

function arabicToGreek(input) {
    'use strict';
    switch (input) {
    case 1:
        return "α";
    case 2:
        return "β";
    case 3:
        return "γ";
    case 4:
        return "δ";
    case 5:
        return "ε";
    case 6:
        return "ϝ";
    case 7:
        return "ζ";
    case 8:
        return "η";
    case 9:
        return "θ";
    case 10:
        return "ι";
    }
    return "";  
}

Usage:

arabicToGreek(4);    
arabicToGreek(10);

Output:

δ
ι

Run it at repl.it

I'm aware ϝ (6) should possibly be written as ϛ. I'm also aware I may or may not need to include diacritics.

I'm especially looking for a review on the usual suspects: naming, idiomatic style and modularity. All other advice is welcome as well.

Reviewing your current structure: your return ""; could be improved: it should / could be inside the switch statement as a default case.

It's better to use an object here, as later you can extend it without having to spend pointless LoCs on cases and breaking.

function arabicToGreek(input) {
    'use strict';
    var greek = {
        1: "α",
        2: "β",
        3: "γ",
        4: "δ",
        5: "ε",
        6: "ϝ",
        7: "ζ",
        8: "η",
        9: "θ",
        10: "ι"
    };
    //
}

Then, add greek.hasOwnProperty to check that your string is a valid object property, in which case that it isn't, you can throw an error.

if (!greek.hasOwnProperty(input)){
    throw new Error("input not a valid integer representing a character");
}

This also means you can store the greek characters and potentially other languages in an external JSON document.

StackExchange Code Review Q#116875, answer score: 13