learn-rust/learning-records/0001-recognition-without-production.md

Recognition without production: ch1–9 is recall-only, writing ability is gone

Diagnostic (lesson 0001, 18 questions across ch1–9) scored 8/18, but the decisive signal was the user's own report: "I even forgot how to write the code." Recognition of concepts is partially intact; production from a blank file is not. Future lessons must be typing-first — quizzes measure this gap but do not close it.

Evidence — self-graded diagnostic, 2026-08-28:

• Weak: Ownership 1/2, Error Handling 1/2, Data Types 0/1, References & Borrowing 1/2, Enums & Pattern Matching 1/2, Common Collections 1/2, Modules & Paths 0/1, Control Flow 0/1
• Solid: Variables 1/1, Structs 2/2, Functions 1/1, Slices 1/1

Implications

• Every lesson from 0002 on must have the user typing real code in a real cargo project, with cargo run / cargo test as the feedback loop. Pure quiz lessons are diagnostic instruments only.
• The user explicitly asked to cover "solid" topics too — treat the diagnostic as weighting, not as a filter. Solid topics get folded into lessons as supporting material rather than skipped.
• "Solid" results here are low-confidence: 1/1 and 2/2 samples, self-graded, on recognition-style questions. Do not treat Structs/Functions/Slices as owned until seen in produced code.
• A syntax reference was the missing prerequisite — forgotten syntax was consuming the working memory needed for concepts. reference/rust-syntax.html now exists and should be linked from every lesson.
• Modules & Paths (0/1) is untouched by lesson 0002 beyond mod tests. It needs its own lesson, and the user's existing restauran/learn-modules projects are the natural material.