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
Reduce an expression from the inside outward
An expression describes a value. Its subexpressions must be evaluated in an order that respects grouping and operator precedence. You can make that order visible by replacing one complete subexpression at a time while preserving the rest.
For (2 + 3) * 4, first reduce the parenthesized 2 + 3 to 5, giving 5 * 4, then 20. Compare 2 + 3 * 4: multiplication reduces first to 12, giving 2 + 12, then 14. The digits are identical; the grouping changes the computation.
Do not read every expression strictly left to right regardless of operators. Also do not remove parentheses merely because they look decorative: they may express the exact rule the author intended. In a mod balance formula, put the grouping in the rule explanation as well as the source.
Worked reasoning and supplied artifact
fnc reward() -> i32 {
return (2 + 3) * 4;
}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 reward() -> i32 {Read the function name, its parameter names/types and the result type after ->. This is the contract the body must satisfy.
return (2 + 3) * 4;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
Write every reduction for (4 + 1) * 3 and 4 + 1 * 3. Predict 15 and 7 respectively.
- 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.
A recipe gives 3 base items and 2 bonus items per batch, with 5 batches. Write the expression for the total. Contrast it with a rule that gives only 2 bonus items overall.
What to produce
Two expressions, reductions to 25 and 17, and a sentence explaining the different scope of the bonus.
- 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?
For (2 + 3) * 4, first reduce the parenthesized 2 + 3 to 5, giving 5 * 4, then 20. Compare 2 + 3 * 4: multiplication reduces first to 12, giving 2 + 12, then 14. The digits are identical; the grouping changes the computation.
Do not read every expression strictly left to right regardless of operators. Also do not remove parentheses merely because they look decorative: they may express the exact rule the author intended. In a mod balance formula, put the grouping in the rule explanation as well as the source.
Original learning-path task and reference
In a racing checkpoint editor, demonstrate values, expressions, and arithmetic. Read the source-grounded example and predict its observable behavior before making changes. 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.
- Reduce an expression from the inside outward
- An expression describes a value. Its subexpressions must be evaluated in an order that respects grouping and operator precedence. You can make that order visible by replacing one complete subexpression at a time while preserving the rest.
- Separate source-backed behavior, host requirements and untested predictions.
One small recap task
Underline the first reducible part of (6 + 2) * 3.
This marks your personal practice record only. It is not a certification or an official workspace assessment.