javascript - Why can Errors not be stringified? -

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• is not possible stringify error using json.stringify? 5 answers

why can errors not stringified?

json.stringify(new referenceerror('foo')); // {} 

when example, date more useful:

json.stringify(new date()); // "2015-04-01t10:23:24.749z" 

javascript error objects not enumerable. can verify easily:

new error('test').propertyisenumerable('message'); // -> false 

you can define own tojson function on error object:

object.defineproperty(error.prototype, 'tojson', {     value: function () {         return {value: "test"};     },     configurable: true });  json.stringify(new error()); -> "{value: "test"}"