That's not an associative array. That's an array object abused. It just works because arrays are also objects in JavaScript.

When you're doing arr.prop_1 = "asdf"; or arr['prop 2'] = "1234"; what you're actually doing is monkey patching an object.

People use objects as maps often - but that'll get fixed soon since ES6 (the new version of the standard JS is based on) has Map types.

###When to use an Array

When you have sequential data - a list of numbers for example

When to use a map

When you want to store a key-value mapping.

That's not an associative array. That's an array object abused. It just works because arrays are also objects in JavaScript.

When you're doing arr.prop_1 = "asdf"; or arr['prop 2'] = "1234"; what you're actually doing is monkey patching an object.

People use objects as maps often - but that'll get fixed soon since ES6 (the new version of the standard JS is based on) has Map types.

When to use an Array

When you have sequential data - a list of numbers for example

When to use a map

When you want to store a key-value mapping.