How to get specific time from next day

Question

I want to create a time.Time for an exact point in time the following day (tomorrow). For now I would like to set the hour and minute.

This is the code

Answer 1

Package time

import "time" 

The month, day, hour, min, sec, and nsec values may be outside their usual ranges and will be normalized during the conversion. For example, October 32 converts to November 1.

---

This is more efficient. It minimizes calls to package time functions and methods.

package main

import (
    "fmt"
    "time"
)

func main() {
    now := time.Now()
    fmt.Println(now.Round(0))
    yyyy, mm, dd := now.Date()
    tomorrow := time.Date(yyyy, mm, dd+1, 15, 0, 0, 0, now.Location())
    fmt.Println(tomorrow)
}

Output:

2019-06-21 16:23:06.525478162 -0400 EDT
2019-06-22 15:00:00 -0400 EDT

---

Some benchmarks:

BenchmarkNow-8                  31197811            36.6 ns/op
BenchmarkTomorrowPeterSO-8      29852671            38.4 ns/op
BenchmarkTomorrowJens-8          9523422           124 ns/op

bench_test.go:

package main

import (
    "testing"
    "time"
)

func BenchmarkNow(b *testing.B) {
    for N := 0; N < b.N; N++ {
        now := time.Now()
        _ = now
    }
}

var now = time.Now()

func BenchmarkTomorrowPeterSO(b *testing.B) {
    for N := 0; N < b.N; N++ {
        // now := time.Now()
        yyyy, mm, dd := now.Date()
        tomorrow := time.Date(yyyy, mm, dd+1, 15, 0, 0, 0, now.Location())
        _ = tomorrow
    }
}

func BenchmarkTomorrowJens(b *testing.B) {
    for N := 0; N < b.N; N++ {
        // now := time.Now()
        tomorrow := time.Date(now.Year(), now.Month(), now.Day(), 15, 0, 0, 0, now.Location()).AddDate(0, 0, 1)
        _ = tomorrow
    }
}