Common Code Patterns

Experienced programmers don't solve each problem from scratch. They recognize patterns and apply proven approaches. Here are essential patterns you'll use constantly. The Transform Pattern Convert each element into a new form. Use when you need to change every item in a collection. The Reduce Pattern Combine all elements into a single value. Use for totals, products, finding min/max, or building composite results. The Two-Pass Pattern Sometimes you need information from the entire collection before processing. Make one pass to gather data, another to use it. The transform, reduce, and two-pass patterns are building blocks that combine naturally. Real-world solutions often chain them: reduce the data to compute an aggregate, then transform every element relative to that aggregate. List comp