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Declaring functions ​

Functions are declared through the use of the fn keyword. Like types and values, they can be declared as public through the use of pub.

The main function is a special case, in that it acts as the entry point of the program automatically. The main function must return void or a signed integer, and should not take any arguments. To read commandline arguments you would use the @args() builtin.

An example of a main functions that prints out the arguments, note that @args returns a list[ref u8] containing all the commandline arguments as raw strings:

spectre
pub fn main() void = {
    val arguments = @args()
    for arg in arguments {
        @print("{s}\n", {arg})
    }
}

Extern functions ​

Externs can be declared through the use of the extern fn construct, like so:

spectre
pub extern (C) fn my_malloc(size: usize) = "malloc"

Here we're using the libc malloc as our extern example, but depending on what is linked, you can use any raw C symbol in the place of malloc in the above example.

Other things of note ​

There are no closures. Nested functions do not exist in this language, and for good reason. It decreases the readability of code, and adds unnecessary complexity to the compiler internals for a feature that does not add much value.