Version 0.4

types/main.go

@@ -0,0 +1,136 @@
+package main
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type myFloat = float64
+type myint int
+
+// func (m myFloat) double() myFloat {
+
+// }
+
+type person struct {
+	age  int
+	name string
+}
+
+type student struct {
+	age  int // try swapping these fields
+	name string
+}
+
+func (m myint) double() myint {
+	return m * 2
+}
+
+func main() {
+	var a uint8 = 1
+	var b uint16 = 2
+	var c uint32 = 3
+	var d uint64 = 4
+
+	var e int8 = 1
+	var f int16 = 2
+	var g int32 = 3
+	var h int64 = 4
+
+	var i float32 = 1.1
+	var j float64 = 1.2
+
+	var k bool = true
+
+	var l byte = 'c'
+	var m byte = 99
+	var n rune = '😀'
+	var o rune = 128512
+
+	var p string = "hello"
+
+	var arr = [5]int{}
+	var slice = []int{}
+	var maps = map[int]int{}
+
+	type empty struct{}
+	var x = empty{}
+
+	var y interface{} = x
+
+	var function = func() int {
+		return 42
+	}
+
+	var aliasInt myint = 1
+	var aliasFloat myFloat = 5.0
+
+	fmt.Printf("Type of a=%T, b=%T, c=%T, d=%T\n", a, b, c, d)
+	fmt.Printf("Type of e=%T, f=%T, g=%T, h=%T\n", e, f, g, h)
+	fmt.Printf("Type of i=%T, j=%T\n", i, j)
+	fmt.Printf("Type of k=%T\n", k)
+	fmt.Printf("Type of l=%T, m=%T, n=%T, o=%T\n", l, m, n, o)
+	fmt.Printf("Type of p=%T\n", p)
+	fmt.Printf("Type of arr=%T\n", arr)
+	fmt.Printf("Type of arr=%T\n", slice)
+	fmt.Printf("Type of arr=%T\n", maps)
+	fmt.Printf("Type of x=%T\n", x)
+	fmt.Printf("Type of y=%T\n", y)
+	fmt.Printf("Type of function=%T\n", function)
+	fmt.Printf("Type of aliasInt=%T, aliasFloat=%T\n", aliasInt, aliasFloat)
+	conversion()
+
+	definedTypeConversion(aliasInt)
+	definedTypeConversion(5)
+
+	takesInt(5)
+	// takesInt(aliasInt) // this does not work
+
+	takesFloat(5)
+	takeInt64(5)
+	takeInt8(5) // try passing > 128
+}
+
+func conversion() {
+	var i int = 355 // type int
+	f := float64(i) // type float64
+	b := i != 0     // type bool
+	s := strconv.Itoa(i)
+	by := byte(i)
+
+	ui8 := 250
+	i8 := int8(ui8)
+
+	fmt.Printf("%d\t%f\t%t\t%s\t%c\t%d\t%d\n", i, f, b, s, by, ui8, i8)
+
+	p := person{age: 20, name: "john"}
+	std := student{age: 15, name: "paul"}
+
+	p2 := person(std)
+	s2 := student(p)
+
+	// p2 := *(*person)(unsafe.Pointer(&std))
+	// s2 := *(*student)(unsafe.Pointer(&p))
+
+	fmt.Printf("Type of p=%T, std=%T, p2=%T, s2=%T\n", p, std, p2, s2)
+}
+
+func definedTypeConversion(mi myint) {
+	fmt.Printf("Type of mi=%T\n", mi)
+}
+
+func takesInt(i int) {
+	fmt.Printf("Type of i=%T\n", i)
+}
+
+func takesFloat(f float32) {
+	fmt.Printf("Type of i=%T\n", f)
+}
+
+func takeInt8(i int8) {
+	fmt.Printf("Type of i=%T\n", i)
+}
+
+func takeInt64(i int64) {
+	fmt.Printf("Type of i=%T\n", i)
+}