Arrays, tuples, and ranges

A patrol can keep points in an array, a contact scan can read one element, and a helper can return two related values as a tuple. These shapes keep several values together without hiding how they are used.

The problem

Collection code has details that matter. matrix[row, column] is not the same shape as matrix[row][column]. ^1 counts from the end. A tuple element may be read by a written name or by Item1.

When to reach for it

Use an array construction when you need a fixed sequence of values. Use a struct construction when a value type has named constructor arguments. Use an indexer to read or write an element. Use a range and slice to select a span. Use a tuple to carry several results without declaring a new type, and deconstruct it when each element needs a local name.

To give a field or local an array type, open its type row in the Variables rail. array sits at the top of the type chooser, after var for a local. Choosing it reopens the chooser to ask what the array holds, so the row becomes int[] or Vector2[]. An array of arrays is not offered this way.

See it

The canvas presents each element or constructor argument as a pin. Index, range, from-end, slice, Make Tuple, and Break Tuple nodes keep their own shape when source is parsed back.

Do it

1. Right-click empty canvas and choose the array, struct, Make Tuple, or Break Tuple action you need.
2. For a new array, fill an element slot. Its type settles the array’s element type. Add, remove, or reorder slots to change the collection shape.
3. For a struct, choose its type and constructor, then fill the argument pins.
4. Place an element access and connect the collection plus its index. Choose add index to create another operand for a multi-dimensional access.
5. Use a from-end index for positions such as the last element. The operand remains significant even when it is zero.
6. Build a range with a start, an end, or deliberately open ends, then connect it to a slice.
7. A Make Tuple starts with two slots. Fill both, then choose add pin for another. A named tuple and unnamed tuple with the same ordered element types can connect.
8. Connect a tuple to Break Tuple to create a deconstruction. The resulting locals follow the tuple names where available.
9. Press Compile in the toolbar, then inspect the re-parsed nodes. Author-written array and tuple spellings are retained when their recorded shape has not changed.

You should see

Each collection element, index operand, range end, tuple slot, and deconstructed local remains visible. Multi-index and chained-index forms stay distinct.

Change one thing

Build a three-value tuple, remove its last slot, and undo. Then connect it to Break Tuple and check the local names before Compile.

What it writes

C#

What it writes

C#

var checkpoints = new[] { 2f, 5f, 9f };
var last = checkpoints[^1];
var middle = checkpoints[1..^1];
var result = (coins: 3, score: 30);
var (coins, score) = result;

When it goes wrong

When it goes wrong

Symptom	Check	Fix
The array stays wildcard gray	Check whether any slot has a typed value or wire.	Supply the first element so the array type can settle.
Compile leaves an access unfinished	Look for a missing collection, index, range, or assignment value.	Fill every required pin or remove the unfinished node.
A nested deconstruction refuses	Look for a tuple pattern inside another tuple pattern.	Finish that edit in C#; the parser flattens that shape.

Next

• Enums and data classes
• Loops
• When Compile refuses