IZCode

IZCode - Structured Programming for Stationeers

IZCode replaces IC10 with IZ: a structured language with types, real functions and recursion, on its own virtual machine inside the Programmable Chip.

Write #iz on the first line of a chip and IZCode takes over. Chips without the marker keep running as IC10, so existing builds are unaffected.

WHY IT EXISTS

[table] [tr][th]IC10[/th][th]IZ[/th][/tr] [tr][td]128 lines, 4096 bytes[/td][td]2000 lines, 16000 bytes[/td][/tr] [tr][td]16 registers[/td][td]Named variables managed by the compiler[/td][/tr] [tr][td]jal/ra, limited calls[/td][td]Functions, parameters, returns and recursion[/td][/tr] [tr][td]Restarts every tick[/td][td]Freezes and resumes execution[/td][/tr] [tr][td]Infinite loop hangs the chip[/td][td]VM preempts execution automatically[/td][/tr] [tr][td]Typos found at runtime[/td][td]Compile errors with suggestions[/td][/tr] [tr][td]Everything is a double[/td][td]num, bool, str and dev are type-checked[/td][/tr] [tr][td]HASH("text")[/td][td]Real strings with concatenation and comparison[/td][/tr] [tr][td]Loose registers[/td][td]Arrays, structs and lists[/td][/tr] [/table]

A COMPLETE PROGRAM

#iz
device sensor = d0;
device inlet = d1;

const TARGET = 101.325;

fn main() {
  loop {
    var p = sensor.Pressure;
    inlet.On = p < TARGET - 5.0;
    yield;
  }
}

Execution starts at fn main(). When it returns, the chip stops until restarted.

THE LANGUAGE

Types

• num - 64-bit floating-point number
• bool - Boolean value
• str - Immutable ASCII string
• dev - Device pin d0-d5, or db
• T[N] - Fixed-size arrays
• list - Typed collections
• struct - User-defined structures

num and bool are not interchangeable: if x needs a bool; write if x != 0 for a number.

var counter = 0;
var active: bool = false;
const MAX = 101.325;

Globals keep their values across ticks.

Arrays and Structs

Arrays and structs live in the VM heap, laid out at compile time. No allocator, no GC.

var samples: num[8];

struct Gauge {
  total: num;
  cursor: num;
  samples: num[8];
}

Array length is part of the type; len(a) is compile-time. Aggregates pass by reference.

Lists and Queries

Fixed-size arrays with a count, and LINQ-style queries:

var rooms: list Room[8];

var r: Room;
r.temp = 40;
rooms.add(r);

var mean  = rooms.avg(x => x.temp);
var hot   = rooms.where(x => x.temp > 30);
var worst = rooms.orderByDesc(x => x.temp).first();

Queries:

• where, select, take, skip
• takeWhile, skipWhile
• orderBy, orderByDesc, reverse
• distinct, sum, avg, min, max
• count, any, all
• first, last, firstOr, lastOr
• contains, indexOf, into

A query chain becomes a single loop, with the lambdas inlined: no intermediate lists, no per-element calls.

Devices

Device properties are checked against the game's LogicType table:

var p = sensor.Pressure;
pump.On = true;

Invalid properties are compile errors: Presure answers did you mean Pressure?

db is the device the chip is installed in, and the only way to reach it: nothing can be wired to it. In a circuit housing it is the housing; in a hardsuit it is the suit, so a program can read its own PressureExternal and drive its AC. On a suit the pins are the wearer's slots: d0 helmet, d1 backpack, d2 toolbelt, d3 glasses, d4 and d5 hands.

device self = db;
self.Setting = 1;

isset(dev) tells whether a pin has a device on it right now, so a program drives whatever is there instead of stopping on an empty pin. IC10's sdse.

device helmet = d0;

if isset(helmet) { helmet.On = true; }

Game Constants

The game's named values, spelled as IC10 spells them:

light.Color = Color.Green;
cooler.Mode = AirCon.Cold;

All 30 groups come from the game itself: Color, GasType, SlotClass, Sound, AirCon, PowerMode, EntityState, LogicType and the rest. Each value folds to its number at compile time, and a typo is a compile error with the nearest name.

Batch Operations

Every matching device on the network:

all(StructureWallLight).On = true;
named("Corridor Light").On = false;
named(StructureVolumePump, "north").On = true;

var avg   = all(StructureGasSensor).Pressure;
var total = all(StructureSolarPanel).PowerGeneration.sum();

A bare read averages; sum(), min(), max() and count() collapse it another way.

A selector can be named and then used like a device on a pin:

device led = named(StructureDiode, #"led-dev");
led.On = true;

Prefab names, #"hash" literals and constants cost nothing at runtime.

Text

Strings are real runtime values: variables, parameters, returns, arrays and structs.

var label = "vent-" + side;
all("Structure" + kind).On = true;

Functions: len, hash, char, chr, sub, find, text, fixed, parse.

Numbers become text only through text(x).

Control Flow

• if / else if / else
• while / loop
• for
• break / continue

Ranges support 0..10 and 0..=10. There is no goto or labels. Braces are mandatory.

Functions and Recursion

Functions have typed parameters, return values and recursion.

fn gcd(a: num, b: num) -> num {
  if b == 0 {
    return a;
  }
  return gcd(b, a % b);
}

A call-depth limit turns runaway recursion into a clean error.

Operators and Math

Operators follow C precedence. Prefix: -x, !x and ~x. c ? a : b picks one of two values, IC10's select.

Division by zero follows IEEE-754. Assignment is a statement, so if (a = b) does not compile.