2017-05-18 18:20:02 +00:00
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# go-opt
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2022-08-08 17:01:41 +00:00
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Package **opt** implements an **optional-type**, for the Go programming language.
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2017-05-18 18:20:02 +00:00
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2022-08-08 17:01:41 +00:00
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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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2017-05-18 18:20:02 +00:00
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## Documention
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Online documentation, which includes examples, can be found at: http://godoc.org/github.com/reiver/go-opt
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[![GoDoc](https://godoc.org/github.com/reiver/go-opt?status.svg)](https://godoc.org/github.com/reiver/go-opt)
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2022-08-08 17:14:51 +00:00
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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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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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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 {
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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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