Add Hangul syllable character name generator

hangul.characterNameGeneration.js

@@ -0,0 +1,41 @@
+const {
+  computeSIndex,
+  computeLIndex,
+  computeVIndex,
+  computeTIndex
+} = require("./hangul.computations");
+
+const {
+  JAMO_L_TABLE,
+  JAMO_V_TABLE,
+  JAMO_T_TABLE
+} = require("./hangul.shortNames");
+
+/**
+ * Generates a letter/jamo-derived short name for a given precomposed Hangul syllable
+ *
+ * @param {(string|integer)} s
+ * @returns {string} Unicode Hangul syllable short name
+ */
+function getHangulCharShortName(s) {
+  const SIndex = computeSIndex(s);
+  const LIndex = computeLIndex(SIndex);
+  const VIndex = computeVIndex(SIndex);
+  const TIndex = computeTIndex(SIndex);
+
+  return JAMO_L_TABLE[LIndex] + JAMO_V_TABLE[VIndex] + JAMO_T_TABLE[TIndex];
+}
+
+/**
+ * Constructs a precomposed Hangul syllable name
+ *
+ * Based on "Hangul Character Name Generation" as described in Unicode core
+ * specification for sample code for Hangul algorithms, under section
+ * "3.12 Conjoining Jamo Behavior" (pp. 142-151)
+ *
+ * @param {(string|integer)} s
+ * @returns {string} Unicode Hangul syllable name
+ */
+const getHangulCharName = s => "HANGUL SYLLABLE " + getHangulCharShortName(s);
+
+module.exports = { getHangulCharShortName, getHangulCharName };

hangul.characterNameGeneration.test.js

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+const { getHangulCharName } = require("./hangul.characterNameGeneration");
+const lo = require("unicode/category/Lo");
+
+const hangulCharNames = {
+  가: "ga",
+  나: "na",
+  다: "da"
+};
+
+describe("getHangulCharName function", () => {
+  Object.entries(hangulCharNames).forEach(([hangulChar, expectedShortName]) => {
+    const expectedName = "HANGUL SYLLABLE " + expectedShortName.toUpperCase();
+    const name = getHangulCharName(hangulChar);
+
+    test(`should fetch '${expectedName}' for ${hangulChar}`, () => {
+      expect(name).toBe(expectedName);
+    });
+  });
+});

hangul.shortNames.js

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+module.exports = {
+  JAMO_L_TABLE: [
+    "G",
+    "GG",
+    "N",
+    "D",
+    "DD",
+    "R",
+    "M",
+    "B",
+    "BB",
+    "S",
+    "SS",
+    "",
+    "J",
+    "JJ",
+    "C",
+    "K",
+    "T",
+    "P",
+    "H"
+  ],
+  JAMO_V_TABLE: [
+    "A",
+    "AE",
+    "YA",
+    "YAE",
+    "EO",
+    "E",
+    "YEO",
+    "YE",
+    "O",
+    "WA",
+    "WAE",
+    "OE",
+    "YO",
+    "U",
+    "WEO",
+    "WE",
+    "WI",
+    "YU",
+    "EU",
+    "YI",
+    "I"
+  ],
+  JAMO_T_TABLE: [
+    "",
+    "G",
+    "GG",
+    "GS",
+    "N",
+    "NJ",
+    "NH",
+    "D",
+    "L",
+    "LG",
+    "LM",
+    "LB",
+    "LS",
+    "LT",
+    "LP",
+    "LH",
+    "M",
+    "B",
+    "BS",
+    "S",
+    "SS",
+    "NG",
+    "J",
+    "C",
+    "K",
+    "T",
+    "P",
+    "H"
+  ]
+};