Collections & Loops

// Array (fixed)
var a [3]int               // [0 0 0]

// Slice (dynamic)
s := []int{1, 2, 3}
s = append(s, 4)           // [1 2 3 4]

// Make with capacity
s = make([]int, 0, 10)     // len=0, cap=10

s := []int{1, 2, 3, 4, 5}
s[1:3]                     // [2 3]
len(s)                     // 5

m := map[string]int{"a": 1, "b": 2}
m["c"] = 3

value, ok := m["d"]       // 0, false (not found)
delete(m, "a")

m := make(map[string]int)

for i := 0; i < 10; i++ {
    fmt.Println(i)
}

// Slice
for i, v := range s {
    fmt.Println(i, v)
}

// Map
for k, v := range m {
    fmt.Println(k, v)
}

// Skip index or value
for _, v := range s { ... }
for i := range s { ... }

running := true
for running {
    if done() {
        running = false
    }
}

for i := 0; i < 10; i++ {
    if i%2 == 0 {
        continue
    }
    if i > 7 {
        break
    }
}