Tutorials covering programming languages, type systems, architecture, tooling, and the patterns used to build software that lasts. Each chapter is standalone, built around real examples and verified facts.
State is the data a component owns and can change over time. Props are read-only and come from the parent; state is mutable and belongs to the component itself. When a component’s state changes, React re-renders the component with the new values, and the UI reflects the change. This is the mechanism that makes React…
References are how Rust lets you use a value without taking ownership of it. A reference is a pointer to a value that belongs to someone else, and borrowing is the act of creating a reference. The owner retains responsibility for the value; the borrower has temporary access. The compiler verifies that every borrow is…
The SELECT statement retrieves rows. Without a WHERE clause, it retrieves every row in the table. With a WHERE clause, it retrieves only the rows that match a condition. The WHERE clause is the filter. It is the difference between “give me all the orders” and “give me the orders placed in the last thirty…
CSS Grid is the two-dimensional layout system that complement flexbox’s one dimension. Flexbox arranges items along a single axis; grid arranges them along both rows and columns simultaneously. This makes grid the right tool for page layouts, dashboards, card galleries, and any design where the alignment of items in both directions matters. Tailwind exposes the…
The built-in guards — typeof, instanceof, in — cover a lot of ground, but they can’t express every check. “A string with length greater than zero,” “an object with id as a number and name as a string,” “a Result with ok: true” — those need logic, not a single operator. That’s what user-defined type…
A class is a string. A style is a string. Both can be bound with :class and :style using the same expression syntax as any other attribute. But Vue provides additional syntax for these two attributes specifically, because they are the ones that change most often in response to state. A button’s class depends on…
Chapter 15 covered the three hooks you use every day: constructor, ngOnInit, and ngOnDestroy. This chapter goes deeper. Angular has eight lifecycle hooks, and the remaining five — ngOnChanges, ngDoCheck, ngAfterContentInit, ngAfterContentChecked, ngAfterViewInit, ngAfterViewChecked — handle the phases most components never need but some depend on entirely. They’re the hooks that fire when inputs change,…
The display property is one of the most important CSS properties. It controls how an element is displayed on a webpage and how it behaves in the document flow. Overview of display Values Value Description In Flow? Dimensions? Line Breaks? inline Flows with text ✅ Yes ❌ No ❌ No block Starts on new line,…
A Set is an unordered collection of unique elements. Where a List preserves insertion order and allows duplicates, a Set guarantees that each value appears at most once and provides fast membership tests. The two collections answer different questions: a List is for sequences where order and repetition matter, and a Set is for membership…
Every Dockerfile that installs software, compiles code, or configures a runtime needs to control two things: the values that parameterize the build and the environment in which the application runs. ARG provides build-time variables that exist only during the image build. ENV provides environment variables that persist into the running container. WORKDIR sets the working…