A look back at how Rails 2.x apps loaded CSV data into models, and how modern Rails apps can do it more efficiently today.
Explore different ways to keep arrays unique in Ruby—using `uniq`, `uniq!`, and the `|` operator.
Ruby supports file-level 'magic comments' that instruct the interpreter—most famously for source encoding, but also for freezing strings, shareable constants, and indentation warnings.
In Ruby, modules can provide both namespacing and mixin functionality. Learn how to define module-level functions using module_function and extend self, and the differences between them.
Learn the basics of working with files in Ruby: opening, reading, writing, streaming, and querying file objects efficiently.
