# Hello, World!

```
"Hello, World!".println
```
This calls the `println` function with the argument
`"Hello, World!"` (a string).

`println` then prints the argument (to stdout),
causing it to show up in your terminal.

# Hello, Variable!

To declare a variable in mers, use `:=`:

```
greeting := "Hello, World!"
```

To retrieve its value, simply write its name.

```
greeting.println
```

# Conditions

(todo)

# Functions

Functions represent actions. Many represent transformations from some input to some output.
They are written as `argument -> action`:

```
a -> if a false else true
```

# Types

(todo)

## Type Annotations

## Custom Types

### Defining Custom Types