PART I
Warm-up
Reconnect with a useful idea before starting values, expressions, and arithmetic. 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
Translate a short rule into arithmetic
Begin with quantities and units, then choose operators. A checkpoint bonus of 4 points for each of 3 checkpoints is multiplication; adding an already earned 10 points afterward is addition. Naming the quantities prevents turning every pair of numbers into an arbitrary sum.
The worked helper computes earned + checkpointCount * pointsEach. For (10,3,4), multiply 3 by 4 to obtain 12 bonus points, then add 10 to obtain 22. All intermediate quantities have a meaning: a count times points per checkpoint gives points.
The expression (earned + checkpointCount) * pointsEach mixes points with a count before multiplying. It predicts 52 for these inputs and does not express the stated rule. An integer type alone cannot catch a unit mistake when every quantity uses i32.
Worked reasoning and supplied artifact
fnc score(earned: i32, checkpointCount: i32, pointsEach: i32) -> i32 {
return earned + checkpointCount * pointsEach;
}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
fnc score(earned: i32, checkpointCount: i32, pointsEach: i32) -> i32 {Read the function name, its parameter names/types and the result type after ->. This is the contract the body must satisfy.
return earned + checkpointCount * pointsEach;Evaluate the following expression using the current values, then send its result to the caller. Explain the value; do not confuse it with printed output.
}Close the nested block or value begun earlier. Match it to its opening boundary to keep the structure readable.
Try the guided change
Trace score(6,2,5), labelling 10 as bonus points and 16 as total points.
- 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: Snack-shop calculator. Build a small, understandable change around values, expressions, and arithmetic.
Write a reward helper for 8 existing points and 6 points for each of 4 rescued characters. Give its signature, expression, intermediate product and total. Include the zero-rescues case.
What to produce
A typed helper and cases 8 + 4 * 6 → 32 and 8 + 0 * 6 → 8, with units.
- 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.
Need a hint?
The worked helper computes earned + checkpointCount * pointsEach. For (10,3,4), multiply 3 by 4 to obtain 12 bonus points, then add 10 to obtain 22. All intermediate quantities have a meaning: a count times points per checkpoint gives points.
The expression (earned + checkpointCount) * pointsEach mixes points with a count before multiplying. It predicts 52 for these inputs and does not express the stated rule. An integer type alone cannot catch a unit mistake when every quantity uses i32.
Original learning-path task and reference
In a puzzle-level authoring tool, demonstrate values, expressions, and arithmetic. Create the smallest .ws integration that demonstrates the section contract. Include .ws source and a host-resource contract; compare at least one normal case and one edge case.
fnc add(a: i32, b: i32) -> i32 {
return a + b;
}
fnc main() -> i32 {
return add(2, 3);
}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.
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.
- Translate a short rule into arithmetic
- Begin with quantities and units, then choose operators. A checkpoint bonus of 4 points for each of 3 checkpoints is multiplication; adding an already earned 10 points afterward is addition. Naming the quantities prevents turning every pair of numbers into an arbitrary sum.
- Separate source-backed behavior, host requirements and untested predictions.
One small recap task
Name a semantic mistake i32 alone cannot detect in this formula.
This marks your personal practice record only. It is not a certification or an official workspace assessment.