feat: introduce safeToString

Safe toString resolution, especially useful in case of error reporting

.lint

@@ -35,5 +35,8 @@ predef+ Float32Array
 ./object/first-key.js
 forin
 
+./test
+predef+ Symbol
+
 ./test/reg-exp/#/index.js
 predef+ __dirname

index.js

@@ -1,18 +1,19 @@
 'use strict';
 
 module.exports = {
-	global:   require('./global'),
+	global:       require('./global'),
+	safeToString: require('./safe-to-string'),
 
-	array:    require('./array'),
-	boolean:  require('./boolean'),
-	date:     require('./date'),
-	error:    require('./error'),
-	function: require('./function'),
-	iterable: require('./iterable'),
-	json:     require('./json'),
-	math:     require('./math'),
-	number:   require('./number'),
-	object:   require('./object'),
-	regExp:   require('./reg-exp'),
-	string:   require('./string')
+	array:        require('./array'),
+	boolean:      require('./boolean'),
+	date:         require('./date'),
+	error:        require('./error'),
+	function:     require('./function'),
+	iterable:     require('./iterable'),
+	json:         require('./json'),
+	math:         require('./math'),
+	number:       require('./number'),
+	object:       require('./object'),
+	regExp:       require('./reg-exp'),
+	string:       require('./string')
 };

safe-to-string.js

@@ -0,0 +1,9 @@
+'use strict';
+
+module.exports = function (value) {
+	try {
+		return String(value);
+	} catch (e) {
+		return "<non-stringifiable value>";
+	}
+};

test/safe-to-string.js

@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = function (t, a) {
+	a(t(), 'undefined');
+	a(t(null), 'null');
+	a(t(10), '10');
+	a(t('str'), 'str');
+	a(t({ toString: function () { return 'miszka'; } }), 'miszka');
+	if (typeof Symbol === 'function') a(t(Symbol()), 'Symbol()');
+	a(t(Object.create(null)), '<non-stringifiable value>');
+};