75 lines
1.4 KiB
Markdown
75 lines
1.4 KiB
Markdown
# go-opt
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Package **opt** implements an **optional-type**, for the Go programming language.
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In other programming languages, an **optional-type** might be know as: a **option-type**, or a **maybe-type**.
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## Documention
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Online documentation, which includes examples, can be found at: http://godoc.org/sourcecode.social/reiver/go-opt
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[](https://godoc.org/sourcecode.social/reiver/go-opt)
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## Examples
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Here is an example **optional-type** that can hold a string:
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```go
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import "sourcecode.social/reiver/go-opt"
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//
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var op opt.Optional[string] // the default value is nothing.
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// ...
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if opt.Nothing[string]() == op {
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fmt.Println("nothing")
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}
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// ...
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op = opt.Something("Hello world! 👾")
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// ...
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switch op {
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case op.Nothing[string]():
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//@TODO
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case op.Something("apple"):
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//@TODO
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case op.Something("banana"):
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//@TODO
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case op.Something("cherry"):
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//@TODO
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default:
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//@TODO
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}
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// ...
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value, found := op.Get()
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if found {
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fmt.Println("VALUE:", value)
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} else {
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fmt.Println("nothing")
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}
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```
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## Import
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To import package **opt** use `import` code like the follownig:
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```
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import "sourcecode.social/reiver/go-opt"
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```
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## Installation
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To install package **opt** do the following:
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```
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GOPROXY=direct go get https://sourcecode.social/reiver/go-opt
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```
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## Author
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Package **opt** was written by [Charles Iliya Krempeaux](http://changelog.ca)
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