feat(strings): add initials()

thi-ng · Sep 9, 2021 · 5b8476f · 5b8476f
1 parent a7e1969
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diff --git a/packages/strings/src/index.ts b/packages/strings/src/index.ts
@@ -9,6 +9,7 @@ export * from "./float";
 export * from "./format";
 export * from "./groups";
 export * from "./hollerith";
+export * from "./initials";
 export * from "./int";
 export * from "./interpolate";
 export * from "./join";

diff --git a/packages/strings/src/initials.ts b/packages/strings/src/initials.ts
@@ -0,0 +1,28 @@
+/**
+ * Takes an array of string parts and returns a new string of each part's
+ * initial character. The `mode` arg can be used to customize result casing
+ * (default: uppercase). If `mode` is null, the original casing will be kept.
+ *
+ * @example
+ * ```ts
+ * initials(["alicia", "bella", "carerra"]);
+ * // "ABC"
+ *
+ * initials("shader-ast-GLSL".split("-"))
+ * // "SAG"
+ *
+ * initials("Ludwig van Beethoven".split(" "), null)
+ * // "LvB"
+ * ```
+ *
+ * @param parts
+ * @param mode
+ */
+export const initials = (parts: string[], mode: "u" | "l" | null = "u") => {
+    const res = parts.map((x) => x[0]).join("");
+    return mode === "u"
+        ? res.toUpperCase()
+        : mode === "l"
+        ? res.toLowerCase()
+        : res;
+};