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Hylo

Hello, World!

Tradition says language guides should start with a program that displays “Hello, World!” on the screen. Let’s oblige!

public fun main() {
  print("Hello, World!")
}

Every program in Hylo must define a main function, with no parameters and no return value, as its entry point. Here, main contains a single statement, which is a call to a global function print with a string argument.

The standard library provides an API to interact with the program’s environment. Command line arguments are accessed by reading a constant named Environment.arguments. Return statuses are signaled by calling the global function exit(status:).

To run this program, open it online in Compiler Explorer.

Once you have installed the compiler, you can also follow these steps:

  • Copy that main function into a file called hello.hylo.
  • Run hc hello.hylo && ./hello.