Dart and Flutter Flutter How to create a circular color picker
There could be some packages that provide a circular color picker but I wanted to understand how it's implemented, so I ...
Dart and Flutter 
Dart and Flutter Flutter How to apply gradient color background
To create a beautiful app, a gradient color background could be a good way to implement it. Let's see how to implement i...
Golang Golang Guarantee to process only once by using sync.Once
If a shared resource is needed on multiple goroutines and the initialization must be done only once on one of the gorout...
Golang Golang Use a pointer receiver to define a function for a struct
Do you recognize that there are two ways to define a method for a struct? func (m StructName) FuncName(){ // do somethin...
Golang Golang How/When to use sync.Cond
When should sync.Cond be used instead of channel? Golang provides easy ways for asynchronous processing. As you know, ch...
Golang Golang Set channel direction to prevent usage error
Do you often use a channel? Have you ever considered the channel direction? To use a channel, someone sends data to the ...
JavaScript/TypeScript How to implement efficient Least Recently Used cache (LRU) in TypeScript
This post is the output of this book. If you want to check all the code, go to my repository. What is cache? Cache is a ...
Golang Golang Check variable order in Struct if you must reduce memory usage
A recent computer has enough resources and thus we might not have the opportunity to reduce memory usage. However, it's ...
Golang Golang Dynamic access to a property in a struct
I needed dynamic access to all properties in a struct in unit tests. In my case, the struct has only boolean properties....
Golang Golang Is Compiling Regex In Loop Really Expensive?
A regex is a useful feature to check whether a string contains a special format. If we have many formats, we might want ...