https://github.com/nikolaydubina/go-bitset-example

Go Bitset: benchmarks, examples, analysis
https://github.com/nikolaydubina/go-bitset-example

benchmarking bitset example go golang static-analysis

Last synced: 4 days ago
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Go Bitset: benchmarks, examples, analysis

• Host: GitHub
• URL: https://github.com/nikolaydubina/go-bitset-example
• Owner: nikolaydubina
• License: mit
• Created: 2023-11-02T16:18:27.000Z (about 1 year ago)
• Default Branch: master
• Last Pushed: 2024-05-09T04:51:44.000Z (8 months ago)
• Last Synced: 2024-10-30T14:24:22.577Z (about 2 months ago)
• Topics: benchmarking, bitset, example, go, golang, static-analysis
• Language: Go
• Homepage:
• Size: 10.7 KB
• Stars: 1
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE
  • Codeowners: .github/CODEOWNERS

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README

        
### How to make bitset in Go?

* *zero overhead*

* short syntax for creating sets from values

* set membership, equality, subset

* compile time

   * block of accidental arithmetics

   * block of implicit cast of untyped constants

   * block of all operators except `==` and `!=`

   * block of creating new values

* extending on the idea of [Go Enum](https://github.com/nikolaydubina/go-enum-example)

```go

package permission

var (

	Read    = Permission{0x1}

	Write   = Permission{0x2}

	Execute = Permission{0x4}

)

// Permission is a set implemented as a bitset of single byte.

type Permission struct{ v uint8 }

var ss = map[Permission]string{

	{}:                           "---",

	Read:                         "r--",

	Write:                        "-w-",

	Execute:                      "--e",

	Read.Add(Write):              "rw-",

	Read.Add(Execute):            "r-e",

	Write.Add(Execute):           "-we",

	Read.Add(Write).Add(Execute): "rwe",

}

func (a Permission) String() string { return ss[a] }

func (a Permission) Add(b Permission) Permission { return Permission{a.v | b.v} }

func (a Permission) Contains(b Permission) bool { return b.v&(a.v&b.v) == b.v }

```

### Benchmarks

```bash

$ go test -bench=. -benchmem ./permission

goos: darwin

goarch: arm64

pkg: github.com/nikolaydubina/go-bitset-example/permission

BenchmarkPermission_Add-10         	1000000000	         0.7463 ns/op	       0 B/op	       0 allocs/op

BenchmarkPermission_Contains-10    	1000000000	         0.4688 ns/op	       0 B/op	       0 allocs/op

BenchmarkPermission_String-10      	132117963	         9.080 ns/op	       0 B/op	       0 allocs/op

PASS

ok  	github.com/nikolaydubina/go-bitset-example/permission	3.552s

```

### References

* https://en.wikipedia.org/wiki/Bit_array

* https://en.cppreference.com/w/cpp/utility/bitset

* https://docs.oracle.com/javase/8/docs/api/java/util/BitSet.html

* https://godbolt.org

* https://github.com/nikolaydubina/go-enum-example