Next up, initializing after the declaration. So I like to specify the type, but you don't have to. And then if I try to set x to 100.1, I'll have a problem. This will, if I don't specify, it'll say, well, 100 could be an integer, it'll infer it as an integer. I mean, 100.something, right? But I call it 100 because that's my initial temperature that I want, but I want it to be a floating point value. So, for instance, say I say x = 100, but I really want it to be a floating point. Now, remember, sometimes this is an issue because maybe it infers something you don't want, right? I like to specify myself, but maybe. So the number 100 is an integer, so it says x must be an integer, makes it an integer. So it will infer the type, it compile with a further type based on the type of the right hand side value. Now, if you do that you're not saying you want it as an integer. And that will make x an integer, it'll declare it as an integer, but it'll also set it equal 100. One way to initialize it is in the declaration itself. So initializing variable values, every variable has to be initialized somehow before you use it.
But we call it an IDnum and it makes things more clear. Also, var pid IDnum, pid is actually an integer. So I can say var temp Celsius, right? And now temp is going to be float64 because float64 is aliased by Celsius. So once you declare a type like this, type Celsius float64 or type IDnum int, you can now declare variables using that alias. I know something about it just based on the name of the type. I want to give it that name IDnum, so that I know every variable that it declares an IDnum, it is an IDnum. I'd like to, I know it's an integer, but I want to name it. So I know this type, this concept ID number. Maybe I want to, maybe I'm making some code that implements a database of users or something. So maybe you want to rename is just to make it clearer for you as a programmer. Now, you can always declare your variables to be float64, but Celsius might make sense in the context of the application, right? Maybe the application is about temperatures. In that case, Celsius is exactly the same as float 64. So you can define a new type, an alias for a new type, type Celsius float64.
Temperatures are something that it's manipulating, right? And every temperature you want it to be a floating point value, 64 bit floating point value. For instance here, it could help you, say you got you got some kind of application and it's working on temperatures. So sometimes this is useful for clarity inside a particular application. And you can make type declarations where you actually define an alias, an alternate name for a type. So we're talking about variables and we're going to talk about how you initialize them, but first, let's finish up the types.
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