go-functional-options
Functional Options Pattern
Functional options is a pattern where you declare an opaque Option type that records information in an internal struct. The constructor accepts a variadic number of these options and applies them to configure the result.
When to Use
Use functional options when:
- 3+ optional arguments on constructors or public APIs
- Extensible APIs that may gain new options over time
- Clean caller experience is important (no need to pass defaults)
The Pattern
Core Components
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