Hello World

Your first program

Create a file called hello.praia:

print("Hello, World!")

Run it:

praia hello.praia

Basic syntax

Praia uses familiar C-style syntax with some differences.

Variables

Declare variables with let:

let name = "Praia"
let version = 1
let running = true

Functions

Define functions with func:

func greet(name) {
    print("Hello, %{name}!")
}

greet("world")

String interpolation

Use %{expression} inside strings:

let lang = "Praia"
print("%{lang} is fun!")

Comments

// single-line comment

/* multi-line
   comment */

Semicolons

Semicolons are optional. They are useful for one-liners:

praia -c 'let x = 1; let y = 2; print(x + y)'

Running scripts

praia script.praia                # run a file
praia script.praia arg1 arg2      # with arguments (available via sys.args)
praia -c 'print("inline")'       # run a one-liner

Next steps

• Learn about the REPL for interactive use
• Read about variables and types
• See the full operators reference