cmap

concurrent map

Golang map doesn't support concurrent reads and writes, Please see (http://golang.org/doc/faq#atomic_maps and http://blog.golang.org/go-maps-in-action), in case you're using multiple Go routines to read and write concurrently from a map some form of guard mechanism should be in-place.

Concurrent map is a wrapper around Go's map, more specifically around a String -> interface{} kinda map, which enforces concurrency.

usage

Import the package:

import (
	"github.com/streamrail/concurrent-map"
)

and go get it using the goapp gae command:

goapp get "github.com/streamrail/concurrent-map"

The package is now imported under the "cmap" namespace.

example

	// Create a new map.
	map := cmap.New()
	
	// Sets item within map, sets "bar" under key "foo"
	map.Set("foo", "bar")

	// Retrieve item from map.
	tmp, ok := map.Get("foo")

	// Checks if item exists
	if ok == true {
		// Map stores items as interface{}, hence we'll have to cast.
		bar := tmp.(string)
	}

	// Removes item under key "foo"
	map.Remove("foo")

For more examples have a look at concurrent_map_test.go.

Running tests:

go test "github.com/streamrail/concurrent-map"

templating

To generate your own custom concurrent maps please use concurrent_map_template.txt, the file is a base template for type specific maps, from terminal run:

sed 's/\<KEY\>/string/g' concurrent_map_template.go | sed 's/\<VAL\>/int/g' > cmap_string_int.go

This creates a new go source file for a string:int map.

license

MIT (see LICENSE file)