implementation

index.js

@@ -0,0 +1,30 @@
+'use strict';
+
+var isString = require('is-string');
+var isNumber = require('is-number-object');
+var isBoolean = require('is-boolean-object');
+var isSymbol = require('is-symbol');
+var isBigInt = require('is-bigint');
+
+// eslint-disable-next-line consistent-return
+module.exports = function whichBoxedPrimitive(value) {
+	// eslint-disable-next-line eqeqeq
+	if (value == null || (typeof value !== 'object' && typeof value !== 'function')) {
+		return null;
+	}
+	if (isString(value)) {
+		return 'String';
+	}
+	if (isNumber(value)) {
+		return 'Number';
+	}
+	if (isBoolean(value)) {
+		return 'Boolean';
+	}
+	if (isSymbol(value)) {
+		return 'Symbol';
+	}
+	if (isBigInt(value)) {
+		return 'BigInt';
+	}
+};

package.json

@@ -26,6 +26,13 @@
 		"url": "https://github.com/ljharb/which-boxed-primitive/issues"
 	},
 	"homepage": "https://github.com/ljharb/which-boxed-primitive#readme",
+	"dependencies": {
+		"is-bigint": "^1.0.0",
+		"is-boolean-object": "^1.0.0",
+		"is-number-object": "^1.0.3",
+		"is-string": "^1.0.4",
+		"is-symbol": "^1.0.2"
+	},
 	"devDependencies": {
 		"@ljharb/eslint-config": "^14.0.2",
 		"eslint": "^6.1.0"