Practice data and interface integration — Boundary detective

PART I

Warm-up

Reconnect with a useful idea before starting practice data and interface integration. 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

Handle a late report after native owner closure

Connect a report through stable data and view identities. A report pipeline obtains an authorized dataset, applies a documented transformation and presents one coherent result version. Native WUIX composition, query interpretation and temporary caching each have distinct contracts and owners. Proposed integration examples are not executed programs.

Query q103 targets native window W103. W103 closes, then another report window W104 opens. q103 completes with valid rows after both events. No automatic owner transfer is permitted.

Track query identity, data revision, view owner and artifact lifetime from request to display. If a stage fails, preserve valid prior work with an accurate status. Never combine a new heading with stale rows or let a late result update an unrelated owner. Worked case: The result remains associated with q103/W103. Its validity as data does not authorize updating W104. It may be retained as a named artifact only if the separate host retention policy permits.

Compare the tempting alternative: Using a global currentWindow pointer routes the old result to a different user context and can show the wrong report in W104.

Worked reasoning and supplied artifact

// Paper trace / supplied exercise-host contract; no execution claimed.
// Query q103 targets native window W103. W103 closes, then another report window W104 opens. q103 completes with valid rows after both events. No automatic owner transfer is permitted.
// The result remains associated with q103/W103. Its validity as data does not authorize updating W104. It may be retained as a named artifact only if the separate host retention policy permits.

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: Operations reporting utility. Build a small, understandable change around practice data and interface integration.

Trace owner and query identities, then define separate data-retention and UI-update decisions for q103.

What to produce

A two-window late-result table and no-cross-owner-update invariant.

• 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 wdb;
domain Inventory {
    const lowStock = wdb.query({
        from: products,
        select: [id, name, stock],
        where: [[ stock < 10 ]],
        order: { by: stock, direction: ascending }
    });
}

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.

• Handle a late report after native owner closure
• Trace owner and query identities, then define separate data-retention and UI-update decisions for q103.
• Separate source-backed behavior, host requirements and untested predictions.

One small recap task

Name the pair of identities a late result must retain.

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