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Hello World

First of all we are just going to create a file called hello.uv with the following code.

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import "print.uv";

fn main(): int {
    println("Hello World!");

    return 0;
}

Once we have that, simply run the command 

uvc hello.uv

Then you should see the output 

Hello World!

What just went on

Line 1, we imported print.uv, as there is no such file defined in the local directly, uvc instead imported the file from the standard library. That file then defined println amongst other functions for us to use.

Lines 3, is us defining the starting point for our program, fn denoting this is a function, main tells the compiler this is the entry point, the function itself takes no inputs, hence the () - then finally there is : int which tells the compiler this function returns an integer.

Note

Why return an integer? It allows the operating system to know if our program executed successfully. If a program returns 0, then the OS knows the program finished successfully, if it returns any other value (typically 1) then the operating system knows the program failed.

Line 4, we parsed the constant value Hello World to the function println, which then sent the input to the standard output of the system. Hence why we saw it.

Finally line 5, we return 0, as our program executed successfully.

Last update: November 13, 2022