building decentralized apps in go: meet gno

package main

func main() {
    println("Hello, Fosdem! It's Manfred.")
}

package hello

func Hello() string {
    return "hello world"
}

we’re building a user-owned internet
where governance is fair,
development is open,
and innovation is rewarded.

package counter

import "strconv"

var counter int

func Incr() {
    counter += 1
}

func Render(_ string) string {
    return "my decentralized counter: " + strconv.Itoa(counter)
}

package microposts

import (
    "std"
    "time"
)

type Post struct {
    text      string
    author    std.Address
    createdAt time.Time
}

func (p Post) String() string {
    out := p.text + "\n"
    out += "_" + p.createdAt.Format("02 Jan 2006, 15:04") + ", by " + p.author.String() + "_"
    return out
}

package microposts

import (
    "std"
    "time"
)

var posts []*Post // automatically persisted

func CreatePost(text string) {
    posts = append(posts, &Post{
        text:      text,
        author:    std.PrevRealm().Addr(), // provided by env
        createdAt: time.Now(),
    })
}

func Render(_ string) string {
    out := "# Posts\n"
    for i := len(posts) - 1; i >= 0; i-- {
        out += "### Post " + strconv.Itoa(i) + "\n" + posts[i].String()
    }
    return out
}

gnokey maketx call \
       -pkgpath "gno.land/r/leon/fosdem25/microposts" \
       -func "CreatePost" \
       -args "Hello FOSDEM people! Welcome <3" ...

package alice

var x int
func GetX() int  { return x }
func SetX(n int) { x = n }

package bob

import "alice"

func IncrAlice() {
    x := alice.GetX()
    alice.SetX(x + 1)
}

we’re building a user-owned internet
where governance is fair,
development is open,
and innovation is rewarded.