create table users (
  id serial primary key,
  name text not null,
  -- stored: пишется на диск, индексируется
  name_upper text
    generated always as (upper(name)) stored,
  -- virtual: считается на лету
  name_lower text
    generated always as (lower(name)) virtual
);

create table docs (
    id serial primary key,
    body text not null,
    body_fts_simple tsvector
        generated always as (to_tsvector('simple', body)) stored,
    body_fts_en tsvector
        generated always as (to_tsvector('english', body)) stored,
    body_fts_el tsvector
        generated always as (to_tsvector('greek', body)) stored
);

create index on docs using gin (body_fts_simple);
create index on docs using gin (body_fts_en);
create index on docs using gin (body_fts_el);

package main

import "sync"

type MyInt struct {
        mu sync.Mutex
        val int
}

func main() {
        var i MyInt

        i.mu.Lock()      
        i.val++
        i.mu.Unlock()
}

package main

import "bytes"
import "io"
import "os"

func main() {
        var b bytes.Buffer
        b.Write([]byte("Hello world"))
        io.Copy(os.Stdout, &b)
}

package main

import "fmt"
import "strings"

func main() {
        // s := make([]string, 0)
        // s := []string{}
        var s []string

        s = append(s, "Hello")
        s = append(s, "world")
        fmt.Println(strings.Join(s, " "))
}

package main

import "fmt"

type Config struct {
        path string
}

func (c *Config) Path() string {
        if c == nil {
                return "/usr/home"
        }
        return c.path
}

func main() {
        var c1 *Config
        var c2 = &Config{
                path: "/export",
        }
        fmt.Println(c1.Path(), c2.Path())
}

a := 77
b := &a
fmt.Println(*b) // 77

a := new(42)
fmt.Println(*a) // 42

s := "hello"
ps := new(s)
fmt.Println(*ps) // hello

type Point struct { X, Y int }
pp := new(Point{X: 5, Y: 7})
fmt.Println(*pp) // {5 7}

f := func() string { return "GoLang" }
pf := new(f())
fmt.Println(*pf) // GoLang

“RIP всем самописным PointerTo[T any](in T) *T — теперь в стандартной библиотеке есть всё необходимое. Маленькое и незаметное изменение, но с огромным профитом.”