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8,071 PointsWhy is portland, seattle etc not declared with const or let?
This video has a lot of copying and pasting without any real explanations on some parts.
e.g
portland = new City();
seattle = new City('Seattle', 'Washington');
salem = new City('Salem');
vancouver = new City('Vancouver', 'Washington');
Why don't 'portland', 'seattle', 'salem', and 'vancouver' have the let or const keyword in front? Are they not normal variables? Please help!
Tim Oltman
7,730 PointsTim Oltman
7,730 PointsI found this stackoverflow post on the topic. Apparently, any variable can be declared without const, let, or var. For example, in the console, the following works just fine:
From the answer on stackoverflow:
So it seems you can use a variable without declaring it first. Javascript will then look in every scope all the way up to the the global scope looking to overwrite the value of that variable. If it doesn't find it, it will attach it to the global scope. This could be really dangerous because, let's say you're using a package or some code written by somebody else and you don't know what they named their variables. x might be an array of values or an instance of a class and you just overwrote it with the value 5.