compare

Overview ¶

Package compare contains the implementation of the compare plugin, which generates the deriveCompare function.

The deriveCompare function is a maintainable and fast way to implement fast Less functions.

deriveCompare(T, T) bool
deriveCompare(T) func(T) bool

When goderive walks over your code it is looking for a function that:

• was not implemented (or was previously derived) and
• has a predefined prefix.

In the following code the deriveCompare function will be found, because it was not implemented and it has a prefix deriveCompare. This prefix is configurable.

package main

import "sort"

type MyStruct struct {
	Int64     int64
	StringPtr *string
}

func sortStructs(ss []*MyStruct) {
	sort.Slice(ss,  func(i, j int) bool {
			return deriveCompare(ss[i], ss[j]) < 0
	})
}

Supported types:

• basic types
• named structs
• slices
• maps
• pointers to these types
• private fields of structs in external packages (using reflect and unsafe)
• and many more

Unsupported types:

• chan
• interface
• function
• unnamed structs, which are not comparable with the == operator

Example output can be found here: https://github.com/awalterschulze/goderive/tree/master/example/plugin/equal

This plugin has been tested thoroughly.