Design font fallback and licensing checks — Change one requirement

PART I

Warm-up

Reconnect with a useful idea before starting design font fallback and licensing checks. 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

Adapt fallback order to an unavailable primary

Font choice combines visual coverage, metrics, availability and licensing. The source does not grant redistribution rights or guarantee installed fonts. Each exercise supplies a license or coverage fixture; conclusions apply to that fixture rather than giving general legal or platform advice.

Host A has Maple and Cedar; Host B has Cedar only. Both fonts cover Ready. Configured order is Maple, Cedar, and the contract skips unavailable fonts. Maple line height20; Cedar24.

Worked reasoning: Host A selects Maple and line height20. Host B skips Maple, selects Cedar and needs24. Functional coverage survives, but the same fixed-height20 container would clip under B.

Failed alternative: Treating fallback as a visual synonym ignores changed metrics even when all glyphs are covered.

Worked reasoning and supplied artifact

A:Maple available ->Ready in Maple,height20
B:Maple absent ->Cedar available ->Ready in Cedar,height24
Container20:A fits;B exceeds by4

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: Accessible service console. Build a small, understandable change around design font fallback and licensing checks.

Analyze primary height18, fallback height22 and container21 on installed-versus-missing-primary hosts.

What to produce

An availability/resolved-font/measurement table with a fallback layout consequence.

• 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.button;
import wuix.layout;
domain Login {
    const screen = {
        layout: { type: "column", padding: [24, 32], gap: 16 },
        components: [{ type: "text", value: "Welcome back" }]
    };
    fnc show() -> void {
        wuix.mount("main", screen);
    }
}

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.

• Adapt fallback order to an unavailable primary
• Analyze primary height18, fallback height22 and container21 on installed-versus-missing-primary hosts.
• Separate source-backed behavior, host requirements and untested predictions.

One small recap task

Recheck layout whenever fallback changes the actual font.

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