Model ordered lists, nested settings, and typed event configuration — Discover and trace

PART I

Warm-up

Reconnect with a useful idea before starting model ordered lists, nested settings, and typed event configuration. In one or two sentences, describe the input, output or host boundary from the previous exercise that this lesson builds on. If you are arriving directly, skim the worked example first; there is no locked prerequisite.

A rough note is enough. You can revise it after the example.

PART II

Instruction & guided example

Trace list position separately from identity

An ordered collection carries order and identity as different facts. A displayed position may change when elements move; a stable record identity should continue naming the same record. Predict transformations using supplied tiny inputs before choosing a configuration or host API.

Ordered input is [{id:17, name:"Cedar"},{id:42, name:"Ash"},{id:9, name:"Birch"}]. Positions are zero-based for this exercise; identity is the id field. The host preserves supplied order unless an explicit transformation is requested.

Worked reasoning: Position0 contains id17; position1 contains42; position2 contains9. Moving Birch to the front yields identity order9,17,42. Cedar moves to position1 but remains id17.

Failed alternative: Treating position0 as permanent Cedar identity selects Birch after the reorder.

Worked reasoning and supplied artifact

Before positions:0->17;1->42;2->9
After move-to-front:0->9;1->17;2->42
Stable Cedar identity:17
Changed Cedar position:0 ->1

Illustrative example from the proposed WillowScript design. The language and WUIX/WMATH/WDB/WAUDIO/WTMP services are not implemented in the supplied source. This site has no interpreter, VM or native host and does not execute or certify the snippet.

Try the guided change

Reconstruct the supplied worked case first: list its inputs, intermediate decisions and final artifact. Compare each row with the explanation and identify exactly where the rejected alternative fails. Then use the changed inputs in Part IV for independent work.

• Write the supplied inputs and initial state before following the example.
• Reconstruct each intermediate calculation or host decision, then compare with the worked artifact.
• Explain why the contrasting alternative fails before attempting the changed inputs in Part IV.

PART III

Take a breather

Step back after the guided example. Look away from the screen, stretch, or reread your prediction. This is an optional learning pause, not a timer or an assessment gate.

When you return, try to name the lesson’s key idea without copying its wording. If that feels difficult, return to Part II and trace one line rather than restarting the entire lesson.

PART IV

Independent practice

Project context: Reusable configuration workspace. Build a small, understandable change around model ordered lists, nested settings, and typed event configuration.

Trace ids8,3,12 when the last item moves first. Track the selected id3 through the transformation.

What to produce

An identity/position table before and after reorder.

• State the intended behavior in a sentence before editing.
• Use only source-backed syntax and the host services whose contract you have been given.
• Record a normal case and a boundary or unavailable-resource case.
• Label hand predictions separately from anything actually measured in a supplied toolchain.

Syntax colors are a reading aid, not a compiler. The line you are editing stays uncolored until you move to a different line; capitalization is never changed. Drafts stay on this browser and code is not executed.

import wuix.widget;
const button = widget.Button({
    text: "Continue",
    events: {
        click: fnc() -> void {
            navigator.open("dashboard");
        }
    }
});

PART V

Self-check

Use this check to notice what to revisit. It does not award a private course grade, block another page or claim to verify compiled code. Every answer has a learning explanation.

You may keep exploring even if you are unsure. Use the hint, compare the trace, and revise your explanation.

PART VI

Recap & small task

Bring the idea back to the mod feature you are building. A useful recap connects the mechanism to a decision you can make in your own code.

• Trace list position separately from identity
• Trace ids8,3,12 when the last item moves first. Track the selected id3 through the transformation.
• Separate source-backed behavior, host requirements and untested predictions.

One small recap task

Name an item by id before describing where it appears.

This marks your personal practice record only. It is not a certification or an official workspace assessment.