Parsing and ASTs: Lab, Review, and Transfer
This is 55AA-009, week 5, session 2. It focuses on "Parsing and ASTs" and turns the weekly plan into discussable, practicable, and reviewable class artifacts.
Learning Objectives
- Explain where "Parsing and ASTs" fits in this course and what core problem it addresses.
- Analyze a case or system related to "Parsing and ASTs" using today's method.
- Connect the session task to the course outcome: Implement lexing, parsing, and semantic checks.
- Complete the questions, notes, and synthesis required by workshop, exercise, and review.
Prerequisites
- Discrete mathematics, data structures, and systems programming.
- Have read the weekly task: Implement a parser and emit ASTs.
- Be able to record assumptions, evidence, risks, and questions to validate in class.
Preparation
- Open the 55AA-009 course repository, readings, and this week's task brief.
- Write two true/false claims or open questions about "Parsing and ASTs" before class.
- Be ready to show questions, lab notes, or project fragments from the previous meeting.
Class Flow
0-8Review previous conclusionsQuickly review the concept framework and unresolved questions for "Parsing and ASTs".
review
Quickly review the concept framework and unresolved questions for "Parsing and ASTs".
When judging "Parsing and ASTs", what fact should be confirmed first?
Expected answer: First confirm the object, boundary, attacker or user capability, observable evidence, and evaluation criteria.
Follow-up: If that fact is not directly observable, what minimal experiment would you design?
Opening
Today's session focuses on "Parsing and ASTs". We will not treat it as an isolated topic. We place it in the course workflow: define the object and boundary, gather evidence, and turn the result into engineering action.
Parsing and ASTs class demo
Open the example, data, or project fragment related to "Parsing and ASTs".
Parsing and ASTs: lecture video
8-18Lab goal and acceptance criteriaDefine today's deliverable, evaluation criteria, and minimum completion line.
setup
Define today's deliverable, evaluation criteria, and minimum completion line.
When judging "Parsing and ASTs", what fact should be confirmed first?
Expected answer: First confirm the object, boundary, attacker or user capability, observable evidence, and evaluation criteria.
Follow-up: If that fact is not directly observable, what minimal experiment would you design?
Review
Return to the previous discussion. State one important conclusion in a sentence, then state one remaining uncertainty. We will carry those uncertainties into today's analysis.
Parsing and ASTs class demo
For the weekly task "Implement a parser and emit ASTs.", write the object, boundary, evidence, risk, and next action.
Parsing and ASTs: lecture video
18-35Instructor demoDemonstrate how to turn the method into reproducible steps or a project fragment.
demo
Demonstrate how to turn the method into reproducible steps or a project fragment.
Where is the weekly task "Implement a parser and emit ASTs." most likely to fail?
Expected answer: Common failures include unclear goals, insufficient evidence, unreproducible environment, and conclusions without process.
Follow-up: What checklist item would reveal this failure early?
Guided question
Here is the first judgment question: if we know only the conclusion but not the environment, inputs, or evidence, can that conclusion guide engineering decisions? Answer yes or no first, then name your assumptions.
Parsing and ASTs class demo
Open the example, data, or project fragment related to "Parsing and ASTs".
Parsing and ASTs: lecture video
35-58Group labStudents execute the weekly task, record evidence, and mark failure points.
lab
Students execute the weekly task, record evidence, and mark failure points.
Where is the weekly task "Implement a parser and emit ASTs." most likely to fail?
Expected answer: Common failures include unclear goals, insufficient evidence, unreproducible environment, and conclusions without process.
Follow-up: What checklist item would reveal this failure early?
Explanation
For "Parsing and ASTs", the key is not memorizing definitions but following an analysis order: define the object, list boundaries, state who can do what, find observable evidence, and turn the conclusion into a task or test.
Parsing and ASTs class demo
For the weekly task "Implement a parser and emit ASTs.", write the object, boundary, evidence, risk, and next action.
Parsing and ASTs: demo and review video
58-70Peer reviewExchange results and check reproducibility, explanation quality, and missed risks.
review
Exchange results and check reproducibility, explanation quality, and missed risks.
What makes a lab result reviewable by someone else?
Expected answer: It needs environment, commands, inputs, outputs, failure conditions, screenshots or logs, and explanations for anomalous results.
Follow-up: How would you write this requirement into homework or project acceptance criteria?
Practice transition
Now apply that order to the weekly task: Implement a parser and emit ASTs. Do not write only the final answer; preserve how you ruled out alternatives.
Parsing and ASTs class demo
Open the example, data, or project fragment related to "Parsing and ASTs".
Parsing and ASTs: demo and review video
70-80In-class revisionRevise notes, code, configuration, models, or report structure based on review feedback.
fix
Revise notes, code, configuration, models, or report structure based on review feedback.
What makes a lab result reviewable by someone else?
Expected answer: It needs environment, commands, inputs, outputs, failure conditions, screenshots or logs, and explanations for anomalous results.
Follow-up: How would you write this requirement into homework or project acceptance criteria?
Summary
Today's deliverable is not polished prose. It is a set of reviewable judgments. After class, complete the required evidence, commands, screenshots, logs, or review notes.
Parsing and ASTs class demo
For the weekly task "Implement a parser and emit ASTs.", write the object, boundary, evidence, risk, and next action.
Parsing and ASTs: demo and review video
80-87Selected sharingSelect two or three groups to explain findings, tradeoffs, and next steps.
share
Select two or three groups to explain findings, tradeoffs, and next steps.
What makes a lab result reviewable by someone else?
Expected answer: It needs environment, commands, inputs, outputs, failure conditions, screenshots or logs, and explanations for anomalous results.
Follow-up: How would you write this requirement into homework or project acceptance criteria?
Summary
Today's deliverable is not polished prose. It is a set of reviewable judgments. After class, complete the required evidence, commands, screenshots, logs, or review notes.
Parsing and ASTs class demo
Open the example, data, or project fragment related to "Parsing and ASTs".
Parsing and ASTs: demo and review video
87-90Submission checkConfirm homework, naming conventions, evidence artifacts, and deadline.
summary
Confirm homework, naming conventions, evidence artifacts, and deadline.
What makes a lab result reviewable by someone else?
Expected answer: It needs environment, commands, inputs, outputs, failure conditions, screenshots or logs, and explanations for anomalous results.
Follow-up: How would you write this requirement into homework or project acceptance criteria?
Summary
Today's deliverable is not polished prose. It is a set of reviewable judgments. After class, complete the required evidence, commands, screenshots, logs, or review notes.
Parsing and ASTs class demo
For the weekly task "Implement a parser and emit ASTs.", write the object, boundary, evidence, risk, and next action.
Parsing and ASTs: demo and review video
Homework
Implement a parser and emit ASTs. Submit lab notes, review feedback, and the next improvement plan.