interfacetricks

Documentation

Index

• func Copy(value interface{}) interface{}
• func CopyObject(in map[string]interface{}) map[string]interface{}
• func Equal(left interface{}, right interface{}) bool
• func Extract(src interface{}, dst interface{}) []error
• func IntersectWith(left interface{}, right interface{}, ...) interface{}
• func Merge(left interface{}, right interface{}) interface{}
• func MergeObjects(left map[string]interface{}, right map[string]interface{}) map[string]interface{}
• func MergeWith(left interface{}, right interface{}, ...) interface{}
• func TopDownWalk(w TopDownWalker, value interface{}) interface{}
• type ExtractError
  • func (e ExtractError) Error() string
• type TopDownWalker

Functions

func Copy

func Copy(value interface{}) interface{}

Create a copy of a value, so we can modify it in place.

func CopyObject

func CopyObject(in map[string]interface{}) map[string]interface{}

Utility so we don't need to cast.

func Equal

func Equal(left interface{}, right interface{}) bool

Recursively test equality of two value trees.

func Extract

func Extract(src interface{}, dst interface{}) []error

Extract "deserializes" an interface into a target destination, using the "encoding/json" conventions.

No actual serialization happens, which means we can avoid a lot of string copies.

The extraction will try to continue even when errors are encountered and return detailed error information for each problem.

func IntersectWith

func IntersectWith(
	left interface{},
	right interface{},
	resolve func(l interface{}, r interface{}) interface{},
) interface{}

Create a new object or array containing only the parts that were in both trees. The values in the new tree are determined by the resolve argument.

func Merge

func Merge(left interface{}, right interface{}) interface{}

Merges two value trees recursively. If there is a conflict, the right value is retained.

func MergeObjects

func MergeObjects(left map[string]interface{}, right map[string]interface{}) map[string]interface{}

Like `Merge` but has a more useful return type if you're merging objects.

func MergeWith

func MergeWith(
	left interface{},
	right interface{},
	conflict func(interface{}, interface{}) interface{},
) interface{}

MergeWith is like Merge but allows you to customize what happens on a conflict.

func TopDownWalk

func TopDownWalk(w TopDownWalker, value interface{}) interface{}

Types

type ExtractError

type ExtractError struct {
	SrcPath []interface{}
	SrcType reflect.Type
	DstType reflect.Type
}

func (ExtractError) Error

func (e ExtractError) Error() string

type TopDownWalker

type TopDownWalker interface {
	WalkArray([]interface{}) (interface{}, bool)
	WalkObject(map[string]interface{}) (interface{}, bool)

	WalkString(string) (interface{}, bool)
	WalkBool(bool) (interface{}, bool)
}

This is a utility for recursively transforming JSON-like interface values in go.

At every step, the transformer returns the new value as well as an indication of whether or not we should continue.