"txtar <https://pkg.go.dev/golang.org/x/tools/txtar>" is the magic.
In the playground, there's a dropdown on the right - it says "Hello, World!" by default. From here, you can select the example called "Multiple Files". On Thursday, 14 April 2022 at 17:50:14 UTC+1 michael...@gmail.com wrote: > @Brian > That example is a superbly concise explanation go mod. Thanks! And I had > no idea you could specify filenames and modules in the Playground. That's > really useful! > > On Wednesday, April 13, 2022 at 3:11:54 AM UTC-4 Brian Candler wrote: > >> > I am a little bewildered by the new mod configuration. >> >> It's as simple as this: >> >> go mod init blah >> go mod tidy >> >> You can put anything(*) for "blah". Literally "blah" will work. It's just >> whatever name you want to give your module. However if you plan to publish >> your module on github then using "github.com/name/project" allows it to >> be found automatically (**). >> >> "go mod tidy" reads through your source code, finds the imported >> dependencies, and fetches them for you. After that, a "go build" or "go >> run" will work. If you add or remove dependencies, run "go mod tidy" again. >> >> These commands create "go.mod" and "go.sum" files. They become part of >> your source code - i.e. you should check them in if you are using a source >> control system. >> >> If you create additional packages in subdirectories, then those packages >> are referenced in import statements as <modulename>/<subdir>. You only need >> one go.mod at the top level. >> Example: https://go.dev/play/p/GgHLoOuHtUH >> >> HTH, >> >> Brian. >> >> (*) OK, not quite anything: there are some lexical constraints. >> https://go.dev/ref/mod#go-mod-file-ident >> (**) See >> https://go.dev/ref/mod#module-path >> >> On Wednesday, 13 April 2022 at 07:35:13 UTC+1 yan.z...@gmail.com wrote: >> >>> Thank you Steven. >>> I am a little bewildered by the new mod configuration. Will it compile >>> If I download the source file from the new github source to src directory >>> without further setting up a mod in the old fashioned way? I am using >>> go1.15. >>> >>> And today I ran a test logging all the sendings to Redis and readings >>> from Redis. It is fine - nothing went wrong. But >>> AnotherRedisDesktopManager still shows the same string format - which I >>> guess is due to it is 32bit and fail to transfer a long decimal to float32. >>> >>> So nothing is wrong in golang or its open-source package. >>> >>> On Tue, Apr 12, 2022 at 9:56 PM Steven Hartland <ste...@multiplay.co.uk> >>> wrote: >>> >>>> First off, the package you're using for redis isn't maintained; you >>>> should switch to github.com/gomodule/redigo/redis instead, which will >>>> allow you to remove the c == nil check as that doesn't happen. >>>> >>>> In your example you're ignoring error from json.Marshal which could be >>>> hiding a problem, so I would recommend you handle that. >>>> >>>> encoding/json should represent float as a json number so I would never >>>> expect what you're seeing but its not clear to me if that is down to how >>>> you are viewing it. >>>> >>>> On Tue, 12 Apr 2022 at 04:02, Zhaoxun Yan <yan.z...@gmail.com> wrote: >>>> >>>>> The scenario is upon receiving an incoming financial quotation, save >>>>> it as a string of json into a Redis service. Sorry but I cannot provide >>>>> the >>>>> whole code of quotation receiving here, which is very complex with cgo. >>>>> But >>>>> the code below will help you get a glimpse on what should be going on: >>>>> >>>>> import ( >>>>> "encoding/json" >>>>> //"errors" >>>>> "fmt" >>>>> "time" >>>>> >>>>> "github.com/garyburd/redigo/redis" >>>>> ) >>>>> >>>>> var pool *redis.Pool >>>>> >>>>> type Fvprices struct { >>>>> P float64 `json:"price"` >>>>> F float64 `json:"floor"` >>>>> C float64 `json:"ceiling"` >>>>> S float64 `json:"settle"` >>>>> T int64 `json:"time"` >>>>> } >>>>> >>>>> func init() { >>>>> pool = newPool() >>>>> } >>>>> >>>>> var redisport = "6379" >>>>> var redisip = "127.0.0.1" >>>>> var password = "" >>>>> >>>>> func newPool() *redis.Pool { >>>>> >>>>> fmt.Println("redis @", redisport, redisip, password) >>>>> return &redis.Pool{ >>>>> MaxIdle: 4, >>>>> MaxActive: 50, // max number of connections >>>>> IdleTimeout: 30 * time.Second, >>>>> >>>>> Dial: func() (redis.Conn, error) { >>>>> c, err := redis.DialURL("redis://" + redisip + ":" + >>>>> redisport) >>>>> if err != nil { >>>>> ErrMsg = fmt.Sprintf("redis connection error: %s", >>>>> err.Error()) >>>>> fmt.Println(time.Now().Format("2006-01-02 15:04:05"), >>>>> ErrMsg) >>>>> return nil, err >>>>> } >>>>> if _, autherr := c.Do("AUTH", password); autherr != nil { >>>>> ErrMsg = fmt.Sprintf("redis password error: %s", err. >>>>> Error()) >>>>> fmt.Println(time.Now().Format("2006-01-02 15:04:05"), >>>>> ErrMsg) >>>>> return nil, autherr >>>>> } >>>>> return c, nil >>>>> }, >>>>> } >>>>> } >>>>> >>>>> func Upfutureprice(future_id string, >>>>> future_price, lowerLimitPrice, upperLimitPrice, preSettlementPrice >>>>> float64, >>>>> updatetime time.Time) { >>>>> >>>>> c := pool.Get() >>>>> if c == nil { >>>>> return >>>>> } >>>>> defer c.Close() >>>>> >>>>> content := Fvprices{ >>>>> P: future_price, >>>>> F: lowerLimitPrice, >>>>> C: upperLimitPrice, >>>>> S: preSettlementPrice, >>>>> T: updatetime.UnixNano() / 1e6, >>>>> } >>>>> >>>>> js, _ := json.Marshal(content) >>>>> >>>>> if _, err := c.Do("SET", future_id, js); err != nil { >>>>> fmt.Println("cannot save to redis：", err) >>>>> } >>>>> } >>>>> >>>>> So obviously until the function "Upfutureprice" everything is >>>>> correct, for all four prices it receives are in float64 format. After >>>>> running this program for one day, I just browse the redis using >>>>> AnotherRedisDesktopManager via ssh port forwarding, and something strange >>>>> happens as I clicking on various future_id key strings: >>>>> >>>>> { >>>>> price:807 >>>>> floor:720.6 >>>>> ceiling:881 >>>>> settle:"800.8000000000001" >>>>> time:1649726499000 >>>>> } >>>>> >>>>> { >>>>> price:"3691.0000000000005" >>>>> floor:3237 >>>>> ceiling:4204 >>>>> settle:3721 >>>>> time:1649726910500 >>>>> } >>>>> >>>>> { >>>>> price:"15405.000000000004" >>>>> floor:13625 >>>>> ceiling:17340 >>>>> settle:15485 >>>>> time:1649728303500 >>>>> } >>>>> >>>>> { >>>>> price:"800.4000000000001" >>>>> floor:720.6 >>>>> ceiling:881 >>>>> settle:"800.8000000000001" >>>>> time:1649728048000 >>>>> } >>>>> >>>>> Note quotations above. I wonder how encoding/json can made >>>>> transformation from a float64 inside struct Fvprices to a string >>>>> instead? It seems that only long decimals would trigger such an error >>>>> while >>>>> short decimals won't: >>>>> >>>>> { >>>>> price:2910 >>>>> floor:2443.5 >>>>> ceiling:3305.5 >>>>> settle:2874.5 >>>>> time:1649728261026 >>>>> } >>>>> >>>>> How could that happen? I am really puzzled. >>>>> >>>>> Regards, >>>>> Zhaoxun >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "golang-nuts" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to golang-nuts...@googlegroups.com. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/golang-nuts/f42b29b3-de17-48c6-9f71-1176f1288396n%40googlegroups.com >>>>> >>>>> <https://groups.google.com/d/msgid/golang-nuts/f42b29b3-de17-48c6-9f71-1176f1288396n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/ce7770ff-d54c-4221-8b6c-d7ee0529ce5dn%40googlegroups.com.
