Lab: think in systems

Apply systems thinking, structure, and complexity to concrete design calls.

Lab · optionalFundamentalsIntermediate11 min

Recommended first

By the end of this lesson you will be able to:

Optional scenario lab. Practice using the systems-and-structure ideas as judgment calls — the way you'd apply them reviewing a design or a diff.

1.
Which function is pure?
One that returns a + bOne that returns a + b and writes to a log fileOne that returns the current timeOne that increments a global counter
2.
A one-line change forces edits across ten files. This is a symptom of:
High cohesionHigh couplingGood architectureLow complexity
3.
Your code repeatedly asks "is this value in the collection?" over a large set of items. Best structure?
A listA setA stackA string
4.
A loop nested inside another loop, both over the same large list, is roughly:
O(1)O(n)O(n squared)O(log n)

The habit to keep: see code as flows, watch the side effects and the coupling, and let the operations pick the structure.

Finished reading? Mark it complete to track your progress.

Performance and tradeoffs

When to care about speed, how to find the real bottleneck, and what you trade for it.

Writing a README people use

The front door of every project — what it must answer, and in what order.