Notes on software and the ideas behind it

Find the meaning
behind the code.

I’m Fred Yang. I write about software—how it works, why it behaves the way it does, and the ideas that make code easier to reason about.

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Working notes / 2026

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Architecture, reactivity, and the hidden relationships that shape frontend systems.

typescript

Demystify typescript keyword type and typeof

In typescript, keyword 'type' is used to alias existing types or anonymous types. This is typescript feature, and it has nothing to do with JavaScript. While const/let are used to declare variable in JavaScript....
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angular

When the change detector of OnPush component of Angular runs?

There are lots posts about how change detector works in Angualr. But I can't find a simple answer about when the change detector runs in OnPush components. I assume you understand how change detection...
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angular

Create an Angular demo project

When learning Angular or any other framework or we have an idea, we want to quickly create a proof of concept. One way is quickly to quickly go to a online editor, such stackblitz,...
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typescript

Angular component field initialization

In my previous post, I talked about Class field initialization in typescript. How about field initialization of angular component, is it different? Angular component is defined an typescript class. It should follow same logics....
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typescript

Please your library user with typescript generic

In typescript, generic is a tool that api/library author to please its consumer. What does this means.
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