Add source codes

Author: akisoqls

.gitignore

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+.DS_Store

README.md

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+# Random String Generator
+
+Returns a random string.
+
+## examples
+
+```JavaScript
+generateRandomString(10); // "hm57vp5J4r"
+generateRandomString(8, ["a","p","P","l","e"]); // "PalalPae"
+generateRandomString(16, "orange-peel") // "-ag-laagn-n-lra-"
+generateRandomString(); // "AgZPEhZVUZRKDSKRctlgx5iibRPdWN8jCOjLxpr8ZnVT9Y9fWl9syJP8gSXjUlr8"
+```
+
+## params
+
+- **`length` (optional)**: The length of random string. Default: `64`
+- **`charset` (optional)**:  Characters used in random string. Default: `abcdefghijklmnoqprstuvwxyzABCDEFGHIJKLMNOQPRSTUVWXYZ0123456789`
+
+## returns
+
+Returns a string that includes randomly selected characters from the charset.

mod.ts

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+/**
+ * Generate random string.
+ * 
+ * @param { number | undefined } length - The length of random string. Default: `64`
+ * @param { string[] | string | undefined } charset - Characters used in random string. Default: `abcdefghijklmnoqprstuvwxyzABCDEFGHIJKLMNOQPRSTUVWXYZ0123456789`
+ * @returns { string } Generated random string.
+ * 
+ * @example
+ * ```JavaScript
+ * generateRandomString(10); // "hm57vp5J4r"
+ * generateRandomString(8, ["a","p","P","l","e"]); // "PalalPae"
+ * generateRandomString(16, "orange-peel") // "-ag-laagn-n-lra-"
+ * generateRandomString(); // "AgZPEhZVUZRKDSKRctlgx5iibRPdWN8jCOjLxpr8ZnVT9Y9fWl9syJP8gSXjUlr8"
+ * ```
+ */
+
+export const generateRandomString = (
+  length = 64,
+  charset: string[] | string = [
+    "a", "b", "c", "d", "e", "f", "g", "h", "i",
+    "j", "k", "l", "m", "n", "o", "p", "q", "r",
+    "s", "t", "u", "v", "w", "x", "y", "z", "A",
+    "B", "C", "D", "E", "F", "G", "H", "I", "J",
+    "K", "L", "M", "N", "O", "P", "Q", "R", "S",
+    "T", "U", "V", "W", "X", "Y", "Z", "0", "1",
+    "2", "3", "4", "5", "6", "7", "8", "9"
+  ]
+): string => {
+  return Array.from(Array(length)).reduce((prev, curr) => {
+    curr = prev + charset[Math.floor(Math.random() * charset.length)];
+    return curr
+  }, "");
+}