packer-cn/vendor/github.com/stretchr/objx/doc.go

67 lines
2.1 KiB
Go

/*
Objx - Go package for dealing with maps, slices, JSON and other data.
Overview
Objx provides the `objx.Map` type, which is a `map[string]interface{}` that exposes
a powerful `Get` method (among others) that allows you to easily and quickly get
access to data within the map, without having to worry too much about type assertions,
missing data, default values etc.
Pattern
Objx uses a preditable pattern to make access data from within `map[string]interface{}` easy.
Call one of the `objx.` functions to create your `objx.Map` to get going:
m, err := objx.FromJSON(json)
NOTE: Any methods or functions with the `Must` prefix will panic if something goes wrong,
the rest will be optimistic and try to figure things out without panicking.
Use `Get` to access the value you're interested in. You can use dot and array
notation too:
m.Get("places[0].latlng")
Once you have sought the `Value` you're interested in, you can use the `Is*` methods to determine its type.
if m.Get("code").IsStr() { // Your code... }
Or you can just assume the type, and use one of the strong type methods to extract the real value:
m.Get("code").Int()
If there's no value there (or if it's the wrong type) then a default value will be returned,
or you can be explicit about the default value.
Get("code").Int(-1)
If you're dealing with a slice of data as a value, Objx provides many useful methods for iterating,
manipulating and selecting that data. You can find out more by exploring the index below.
Reading data
A simple example of how to use Objx:
// Use MustFromJSON to make an objx.Map from some JSON
m := objx.MustFromJSON(`{"name": "Mat", "age": 30}`)
// Get the details
name := m.Get("name").Str()
age := m.Get("age").Int()
// Get their nickname (or use their name if they don't have one)
nickname := m.Get("nickname").Str(name)
Ranging
Since `objx.Map` is a `map[string]interface{}` you can treat it as such.
For example, to `range` the data, do what you would expect:
m := objx.MustFromJSON(json)
for key, value := range m {
// Your code...
}
*/
package objx