Control playback volume — Change one requirement

PART I

Warm-up

Reconnect with a useful idea before starting control playback volume. 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.

Recall note

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

PART II

Instruction & guided example

Separate the preference from a per-alert policy

User volume is 0.8. A quiet-hours exercise policy caps effective playback at 0.3 but preserves the stored preference.

Before quiet hours, requested level is 0.8. During quiet hours, the effective level is min(0.8,0.3)=0.3 while the saved preference stays 0.8. Afterward, 0.8 is available again. Replacing the saved preference with the cap loses the user’s chosen setting. This minimum rule is an exercise-host policy, not a claimed WAUDIO feature.

Use the supplied case as a paper design exercise. WillowScript and these library integrations are proposed and unimplemented here; no interpreter or native host has checked the example. Preserve the source API spellings, label new policies as exercise-host contracts, and distinguish a predicted result from measured execution.

Worked reasoning and supplied artifact

// PAPER FIXTURE — Separate the preference from a per-alert policy
// Manual worked artifact; comments below are not executable source.
// INPUT / CONTRACT: User volume is 0.8. A quiet-hours exercise policy caps effective playback at 0.3 but
// preserves the stored preference.
// DERIVATION / EXPECTED ARTIFACT: Before quiet hours, requested level is 0.8. During quiet hours, the
// effective level is min(0.8,0.3)=0.3 while the saved preference stays 0.8. Afterward, 0.8 is available
// again. Replacing the saved preference with the cap loses the user’s chosen setting. This minimum rule is
// an exercise-host policy, not a claimed WAUDIO feature.

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.

Walk through the example, one line at a time

// PAPER FIXTURE — Separate the preference from a per-alert policy
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// Manual worked artifact; comments below are not executable source.
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// INPUT / CONTRACT: User volume is 0.8. A quiet-hours exercise policy caps effective playback at 0.3 but
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// preserves the stored preference.
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// DERIVATION / EXPECTED ARTIFACT: Before quiet hours, requested level is 0.8. During quiet hours, the
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// effective level is min(0.8,0.3)=0.3 while the saved preference stays 0.8. Afterward, 0.8 is available
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// again. Replacing the saved preference with the cap loses the user’s chosen setting. This minimum rule is
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.
// an exercise-host policy, not a claimed WAUDIO feature.
This comment explains intent for a reader. It is not an operation and should not be counted as an executed result.

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.

Prediction or guided notes

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.

Your drafts remain here. Continue whenever you are ready.

PART IV

Independent practice

Project context: Notification control panel. Build a small, understandable change around control playback volume.

Trace preferences 0.2 and 0.9 across quiet-hours entry and exit. Produce separate saved and effective columns.

What to produce

Trace preferences 0.2 and 0.9 across quiet-hours entry and exit. Produce separate saved and effective columns.

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.

Your .ws practice draft

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.

Need a hint?

A temporary policy can alter effective output without overwriting a persistent user choice. Start by writing the distinct intermediate states or arithmetic before changing the source.

Saved 0.3; effective 0.3 forever is the tempting incorrect conclusion in this case. A temporary policy can alter effective output without overwriting a persistent user choice.

Original learning-path task and reference

In a museum exhibit console, demonstrate control playback volume. Adapt the task to a second host-neutral application context without changing the imported API contract. Include .ws source and a host-resource contract; compare at least one normal case and one edge case.

import audio.playback;
domain Notice {
    fnc notify() -> void {
        vary sound = audio.load("notification.wav");
        sound.setVolume(0.75);
        sound.play();
    }
}

Where the original task needs a host API that is not supplied here, write the contract and predictions. Do not invent a runtime result.

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.

For preference 0.8 during quiet hours, what pair fits?Saved 0.8; effective 0.3Saved 0.3; effective 0.3 forever

Explain a normal or boundary case

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.

Separate the preference from a per-alert policy
User volume is 0.8. A quiet-hours exercise policy caps effective playback at 0.3 but preserves the stored preference.
Separate source-backed behavior, host requirements and untested predictions.

One small recap task

Explain why “Saved 0.3; effective 0.3 forever” fails for the supplied case, then give one changed input that would require revisiting your conclusion.

Your recap

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