codewars/books/go_head_first/misc/func.go

package main

import (
	"errors"
	"fmt"
	"log"
	"math"
)

func manyReturns() (int, bool, string) {
	return 1, true, "hello"

	// usage
	// myInt, myBool, myString := manyReturns()
}

func floatParts(number float64) (integerPart int, fractionalPart float64) {
	wholeNumber := math.Floor(number)
	return int(wholeNumber), number - wholeNumber
}

func test_err() {
	// err := errors.New("height can't be negative")
	err := fmt.Errorf("a height of %0.2f is invalid", -2.3333)
	fmt.Println(err)
	log.Fatal(err)
}

func divide(dividend float64, divisor float64) (float64, error) {
	if divisor == 0.0 {
		return 0, errors.New("can't divide by 0")
	}
	return dividend / divisor, nil
}

func paintNeeded(width float64, height float64) (float64, error) {
	if width < 0 {
		return 0, fmt.Errorf("a width of %0.2f is invalid", width)
	}
	if height < 0 {
		return 0, fmt.Errorf("a height of %0.2f id invalid", height)
	}
	area := width * height
	return area / 10, nil
}

func main() {
	quotient, err := divide(5.6, 0.0)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Printf("%0.2f\n", quotient)
	}

	/*
	   var amount float64
	   amount, err := paintNeeded(4.2, 3.0)

	   	if err != nil {
	   		log.Fatal(err)
	   	} else {

	   		fmt.Printf("%0.2f liters needed\n", amount)
	   	}
	*/
}