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• Go Big or Go Home

  - by user12601034

  For those who don’t know, Oracle sponsors a group called “OWL” – Oracle Women’s Leadership - and the purpose of the group is to create local and global opportunities that support, educate and empower current and future women leaders at Oracle. This week, I had the opportunity to attend the Denver OWL roadshow, and I was really impressed with the quality of speakers and interactions that I experienced. One theme that arose throughout the day was that of “Lean In.” In a nutshell, “Lean In” requires you to take advantage of the opportunities that you’re given. One of my personal mantras is “Go big or go home."  That is, if you’re not willing to give it your all, don’t do it at all. Regardless of how you phrase it, it’s a life lesson that I believe needs to be tossed in our face every so often simply, if for no other reason, to get our attention. You are given a finite amount of time in your life; in your job role; in your interactions with others. Do you make the most of the opportunities given to you every day? Or do you believe that life just happens, and you have to deal with whatever is handed to you? I have a challenge for you. Set aside any concerns or fears you have about something and Lean In. Make the most of an opportunity presented to you…or make your own opportunity! If you start with just one thing, you’ll start building a mindset to make the most of additional opportunities. Not only will you be better for leaning in, but I’m betting that those around you will be better for it as well.

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• Go Big or Go Home

  - by Justin Kestelyn

  The Oracle Develop conference (#oracledevelop10), being co-located for the first time ever with JavaOne in San Francisco, is guaranteed to be the ultimate rush for developers this year. Where else can you go to learn about, interact with, and meet fellow devotees of the entire Oracle Development stack (welcome, Oracle Solaris)? This will also be the first time that the community space traditionally located at Oracle OpenWorld - and hosted by Oracle Technology Network, as always - will be present at the "developer" conference during this busy week. So, Oracle OpenWorld's loss is Oracle Develop's gain. And what a community space it will be: nearly 4,000 square feet for meeting space, contests and give-aways, consumption of various beverages, special speakers (Oracle ACEs among them, no doubt), and video-casting. The entire Oracle Technology Network crew will be on hand to "facilitate" your experience, of course. Even better, you can rub shoulders and share war stories with attendees from that "other" conference, JavaOne. (You have access to both conferences as a single package, so you may be having a conversation with yourself.) We call the whole enchilada "The Zone". As time goes on, we'll bring you more news about the activities described above, as well as OTN Night (which proves to be more raucous than ever), technical sessions and keynotes not to be missed, the unconference/open sessions, things to do at night, and more. In the meantime, stay in touch with us via Twitter or Oracle Mix.

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• Joel Spolsky Retires From Blogging in 3 Days

  - by andyleonard

  No it's not 1 Apr. Joel Spolsky ( Blog - @spolsky ) announced recently he is retiring from blogging 17 Mar 2010 . Reading Joel on Software always makes me think. Mr. Spolsky pioneered a writing style. Along the way he empowered developers, encouraging them to speak up about the manifold misconceptions of our trade. I will miss Mr. Spolsky's writings. I wish him well in all his endeavors. :{| Andy Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!...(read more)

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• How Microsoft Lost the API War - by Joel Spolsky

  - by TechTwaddle

  Came across another gem of an article by Joel Spolsky. It's a pretty old article written in June of 2004, has lot of tidbits and I really enjoyed reading it, so much in fact that I read it twice! So hit the link below and give it a read if you haven't already, How Microsoft Lost the API War - Joel Spolsky excerpt, "I first heard about this from one of the developers of the hit game SimCity, who told me that there was a critical bug in his application: it used memory right after freeing it, a major no-no that happened to work OK on DOS but would not work under Windows where memory that is freed is likely to be snatched up by another running application right away. The testers on the Windows team were going through various popular applications, testing them to make sure they worked OK, but SimCity kept crashing. They reported this to the Windows developers, who disassembled SimCity, stepped through it in a debugger, found the bug, and added special code that checked if SimCity was running, and if it did, ran the memory allocator in a special mode in which you could still use memory after freeing it."

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• Add new types to Go

  - by nevalu

  I'm trying add new types for that been managed/used as in Go core types. To create new types is anything very interesting to validate data before of send it to a non-SQL DBMS or to check data from a form. Go uses univeral constants to define them at global level: var DateType = universe.DefineType("date", universePos, &dateType{}) In this case they're defined to be called from a package like types: var Date = &dateType{} I get these errors: test.go:58: o.lit undefined (cannot refer to unexported field lit) test.go:62: *dateType is not Type missing Pos() token.Position The code is based on: http://github.com/tav/go/blob/master/src/pkg/exp/eval/value.go http://github.com/tav/go/blob/master/src/pkg/exp/eval/type.go package main import ( "exp/eval" "fmt" // "go/token" ) // http://github.com/tav/go/blob/master/src/pkg/exp/eval/value.go type DateValue interface { eval.Value Get(*eval.Thread) string Set(*eval.Thread, string) } /* Date */ type dateV string func (v *dateV) String() string { return fmt.Sprint(*v) } func (v *dateV) Assign(t *eval.Thread, o eval.Value) { *v = dateV(o.(DateValue).Get(t)) } func (v *dateV) Get(*eval.Thread) string { return string(*v) } func (v *dateV) Set(t *eval.Thread, x string) { *v = dateV(x) } // http://github.com/tav/go/blob/master/src/pkg/exp/eval/type.go type Type interface { eval.Type // isDate returns true if this is a date type. isDate() bool } /* Common type */ type commonType struct{} // added func (commonType) isDate() bool { return false } /* Date */ type dateType struct { commonType } // * It should not be an universal constant //var universePos = token.Position{"<universe>", 0, 0, 0} // added //var DateType = universe.DefineType("date", universePos, &dateType{}) var Date = &dateType{} func (t *dateType) compat(o Type, conv bool) bool { t2, ok := o.lit().(*dateType) return ok && t == t2 } func (t *dateType) lit() Type { return t } func (t *dateType) isDate() bool { return true } func (t *dateType) String() string { return "<date>" } func (t *dateType) Zero() eval.Value { res := dateV("") return &res } /* Named types */ /* type NamedType struct { eval.NamedType Def Type }*/ type NamedType struct { // added // token.Position Name string // Underlying type. If incomplete is true, this will be nil. // If incomplete is false and this is still nil, then this is // a placeholder type representing an error. Def Type // True while this type is being defined. incomplete bool methods map[string]eval.Method } func (t *NamedType) isDate() bool { return t.Def.isDate() } /* *********************** */ func main() { print("foo") }

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• What can Go chan do that a list cannot?

  - by alpav

  I want to know in which situation Go chan makes code much simpler than using list or queue or array that is usually available in all languages. As it was stated by Rob Pike in one of his speeches about Go lexer, Go channels help to organize data flow between structures that are not homomorphic. I am interested in a simple Go code sample with chan that becomes MUCH more complicated in another language (for example C#) where chan is not available. I am not interested in samples that use chan just to increase performance by avoiding waiting of data between generating list and consuming the list (which can be solved by chunking) or as a way to organize thread safe queue or thread-safe communication (which can be easily solved by locking primitives). I am interested in a sample that makes code simpler structurally disregarding size of data. If such sample does not exist then sample where size of data matters. I guess desired sample would contain bi-directional communication between generator and consumer. Also if someone could add tag [channel] to the list of available tags, that would be great.

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• Go - Using a container/heap to implement a priority queue

  - by Seth Hoenig

  In the big picture, I'm trying to implement Dijkstra's algorithm using a priority queue. According to members of golang-nuts, the idiomatic way to do this in Go is to use the heap interface with a custom underlying data structure. So I have created Node.go and PQueue.go like so: //Node.go package pqueue type Node struct { row int col int myVal int sumVal int } func (n *Node) Init(r, c, mv, sv int) { n.row = r n.col = c n.myVal = mv n.sumVal = sv } func (n *Node) Equals(o *Node) bool { return n.row == o.row && n.col == o.col } And PQueue.go: // PQueue.go package pqueue import "container/vector" import "container/heap" type PQueue struct { data vector.Vector size int } func (pq *PQueue) Init() { heap.Init(pq) } func (pq *PQueue) IsEmpty() bool { return pq.size == 0 } func (pq *PQueue) Push(i interface{}) { heap.Push(pq, i) pq.size++ } func (pq *PQueue) Pop() interface{} { pq.size-- return heap.Pop(pq) } func (pq *PQueue) Len() int { return pq.size } func (pq *PQueue) Less(i, j int) bool { I := pq.data.At(i).(Node) J := pq.data.At(j).(Node) return (I.sumVal + I.myVal) < (J.sumVal + J.myVal) } func (pq *PQueue) Swap(i, j int) { temp := pq.data.At(i).(Node) pq.data.Set(i, pq.data.At(j).(Node)) pq.data.Set(j, temp) } And main.go: (the action is in SolveMatrix) // Euler 81 package main import "fmt" import "io/ioutil" import "strings" import "strconv" import "./pqueue" const MATSIZE = 5 const MATNAME = "matrix_small.txt" func main() { var matrix [MATSIZE][MATSIZE]int contents, err := ioutil.ReadFile(MATNAME) if err != nil { panic("FILE IO ERROR!") } inFileStr := string(contents) byrows := strings.Split(inFileStr, "\n", -1) for row := 0; row < MATSIZE; row++ { byrows[row] = (byrows[row])[0 : len(byrows[row])-1] bycols := strings.Split(byrows[row], ",", -1) for col := 0; col < MATSIZE; col++ { matrix[row][col], _ = strconv.Atoi(bycols[col]) } } PrintMatrix(matrix) sum, len := SolveMatrix(matrix) fmt.Printf("len: %d, sum: %d\n", len, sum) } func PrintMatrix(mat [MATSIZE][MATSIZE]int) { for r := 0; r < MATSIZE; r++ { for c := 0; c < MATSIZE; c++ { fmt.Printf("%d ", mat[r][c]) } fmt.Print("\n") } } func SolveMatrix(mat [MATSIZE][MATSIZE]int) (int, int) { var PQ pqueue.PQueue var firstNode pqueue.Node var endNode pqueue.Node msm1 := MATSIZE - 1 firstNode.Init(0, 0, mat[0][0], 0) endNode.Init(msm1, msm1, mat[msm1][msm1], 0) if PQ.IsEmpty() { // make compiler stfu about unused variable fmt.Print("empty") } PQ.Push(firstNode) // problem return 0, 0 } The problem is, upon compiling i get the error message: [~/Code/Euler/81] $ make 6g -o pqueue.6 Node.go PQueue.go 6g main.go main.go:58: implicit assignment of unexported field 'row' of pqueue.Node in function argument make: *** [all] Error 1 And commenting out the line PQ.Push(firstNode) does satisfy the compiler. But I don't understand why I'm getting the error message in the first place. Push doesn't modify the argument in any way.

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• Why is go language so slow?

  - by oraz

  As we can see from The Computer Language Benchmarks Game: go is in average 10x slower then C go is 3x slower then Java !? How it can be bearing in mind that go compiler produces native code for execution? Immature compilers for go? Or there is some intrinsic problem with the go language?

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• go programming POST FormValue can't be printed

  - by poor_programmer

  Before I being a bit of background, I am very new to go programming language. I am running go on Win 7, latest go package installer for windows. I'm not good at coding but I do like some challenge of learning a new language. I wanted to start learn Erlang but found go very interesting based on the GO I/O videos in youtube. I'm having problem with capturing POST form values in GO. I spend three hours yesterday to get go to print a POST form value in the browser and failed miserably. I don't know what I'm doing wrong, can anyone point me to the right direction? I can easily do this in another language like C#, PHP, VB, ASP, Rails etc. I have search the entire interweb and haven't found a working sample. Below is my sample code. Here is Index.html page {{ define "title" }}Homepage{{ end }} {{ define "content" }} <h1>My Homepage</h1> <p>Hello, and welcome to my homepage!</p> <form method="POST" action="/"> <p> Enter your name : <input type="text" name="username"> </P> <p> <button>Go</button> </form> <br /><br /> {{ end }} Here is the base page <!DOCTYPE html> <html lang="en"> <head> <title>{{ template "title" . }}</title> </head> <body> <section id="contents"> {{ template "content" . }} </section> <footer id="footer"> My homepage 2012 copy </footer> </body> </html> now some go code package main import ( "fmt" "http" "strings" "html/template" ) var index = template.Must(template.ParseFiles( "templates/_base.html", "templates/index.html", )) func GeneralHandler(w http.ResponseWriter, r *http.Request) { index.Execute(w, nil) if r.Method == "POST" { a := r.FormValue("username") fmt.Fprintf(w, "hi %s!",a); //<-- this variable does not rendered in the browser!!! } } func helloHandler(w http.ResponseWriter, r *http.Request) { remPartOfURL := r.URL.Path[len("/hello/"):] fmt.Fprintf(w, "Hello %s!", remPartOfURL) } func main() { http.HandleFunc("/", GeneralHandler) http.HandleFunc("/hello/", helloHandler) http.ListenAndServe("localhost:81", nil) } Thanks! PS: Very tedious to add four space before every line of code in stackoverflow especially when you are copy pasting. Didn't find it very user friendly or is there an easier way?

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• Whats for to use GO

  - by Incognito

  I am interested in new language from Google, GO. I have checked the materials in the golang.com. And now want to use GO in practice. Please share any ideas whats for you are using GO. Or are there any open source GO projects that it would be possible to join?

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• Go programming: How to get from cgo to exe

  - by Kawili-wili

  From a basic test program. . . package main /* #include <stdio.h> static void test() { printf("hello world"); } */ import "C" func main() { C.test(); } I do "cgo hello_cgo.go" and get: _cgo_.o _cgo_defun.c _cgo_gotypes.go hello_cgo.cgo1.go hello_cgo.cgo2.c How do I go about compiling from here to an exe?

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• Wrapping FUSE from Go

  - by Matt Joiner

  I'm playing around with wrapping FUSE with Go. However I've come stuck with how to deal with struct fuse_operations. I can't seem to expose the operations struct by declaring type Operations C.struct_fuse_operations as the members are lower case, and my pure-Go sources would have to use C-hackery to set the members anyway. My first error in this case is "can't set getattr" in what looks to be the Go equivalent of a default copy constructor. My next attempt is to expose an interface that expects GetAttr, ReadLink etc, and then generate C.struct_fuse_operations and bind the function pointers to closures that call the given interface. This is what I've got (explanation continues after code): package fuse // #include <fuse.h> // #include <stdlib.h> import "C" import ( //"fmt" "os" "unsafe" ) type Operations interface { GetAttr(string, *os.FileInfo) int } func Main(args []string, ops Operations) int { argv := make([]*C.char, len(args) + 1) for i, s := range args { p := C.CString(s) defer C.free(unsafe.Pointer(p)) argv[i] = p } cop := new(C.struct_fuse_operations) cop.getattr = func(*C.char, *C.struct_stat) int {} argc := C.int(len(args)) return int(C.fuse_main_real(argc, &argv[0], cop, C.size_t(unsafe.Sizeof(cop)), nil)) } package main import ( "fmt" "fuse" "os" ) type CpfsOps struct { a int } func (me *CpfsOps) GetAttr(string, *os.FileInfo) int { return -1; } func main() { fmt.Println(os.Args) ops := &CpfsOps{} fmt.Println("fuse main returned", fuse.Main(os.Args, ops)) } This gives the following error: fuse.go:21[fuse.cgo1.go:23]: cannot use func literal (type func(*_Ctype_char, *_Ctype_struct_stat) int) as type *[0]uint8 in assignment I'm not sure what to pass to these members of C.struct_fuse_operations, and I've seen mention in a few places it's not possible to call from C back into Go code. If it is possible, what should I do? How can I provide the "default" values for interface functions that acts as though the corresponding C.struct_fuse_operations member is set to NULL?

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• Best way to organize a Go interface

  - by Metropolis

  Hey Everyone, Its been a long time since I have programmed in C++, and if I remember correctly the best way to organize classes was to create your class in the .h file, and then your implementation in your .cpp file. Well I am trying to learn Go now and I was reading over the Go for C++ Programmers article when I came upon interfaces. The article explains that interfaces in Go essentially take the place of classes, and shows how to set them up pretty well. What I am trying to figure out though is how should I organize an interface into files? For instance, should the interface be in one file while the implementation is in another? myInterface.go type myInterface interface { get() int set(i int) } myImplementation.go type myType struct { i int } func (p *myType) set(i int) { p.i = i } func (p *myType) get() int { return p.i } My code here may be wrong since I do not completely know what I am doing yet (and if I am wrong please correct me), but would this be the best way to set this up? Im having a very hard time trying to wrap my head around how to organize code in Go so any help is appreciated! Metropolis

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• web.go install error

  - by Metropolis

  Hey Everyone, I am trying to install web.go using goinstall github.com/hoisie/web.go, and I keep getting an error about the path. goinstall: github.com/hoisie/web.go: git: no such file or directory goinstall is working for sure because when I type in just goinstall I get the options list for it. Any ideas on what I am doing wrong? Metropolis

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• Why does Go compile quickly?

  - by Evan Kroske

  I've Googled and poked around the Go website, but I can't seem to find an explanation for Go's extraordinary build times. Are they products of the language features (or lack thereof), a highly optimized compiler, or something else? I'm not trying to promote Go; I'm just curious.

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• Anti-Joel Test

  - by Vaibhav Garg

  The Joel Test is a measure of how a team performs with regards to the best practices in coding. What questions, given a 'yes' answer, would subtract from the the Joel test score? (Assuming you don't simply negate the current questions on the 'Joel Test', ie: "Do you have no source control?") For example: Does the company insist on being very process heavy?

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• Go XML Unmarshal example doesn't compile

  - by marketer

  The Xml example in the go docs is broken. Does anyone know how to make it work? When I compile it, the result is: xmlexample.go:34: cannot use "name" (type string) as type xml.Name in field value xmlexample.go:34: cannot use nil as type string in field value xmlexample.go:34: too few values in struct initializer Here is the relevant code: package main import ( "bytes" "xml" ) type Email struct { Where string "attr"; Addr string; } type Result struct { XMLName xml.Name "result"; Name string; Phone string; Email []Email; } var buf = bytes.NewBufferString ( ` <result> <email where="home"> <addr>[email protected]</addr> </email> <email where='work'> <addr>[email protected]</addr> </email> <name>Grace R. Emlin</name> <address>123 Main Street</address> </result>`) func main() { var result = Result{ "name", "phone", nil } xml.Unmarshal ( buf , &result ) println ( result.Name ) }

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• runtime error: invalid memory address or nil pointer dereference

  - by Klink

  I want to learn OpenGL 3.0 with golang. But when i try to compile some code, i get many errors. package main import ( "os" //"errors" "fmt" //gl "github.com/chsc/gogl/gl33" //"github.com/jteeuwen/glfw" "github.com/go-gl/gl" "github.com/go-gl/glfw" "runtime" "time" ) var ( width int = 640 height int = 480 ) var ( points = []float32{0.0, 0.8, -0.8, -0.8, 0.8, -0.8} ) func initScene() { gl.Init() gl.ClearColor(0.0, 0.5, 1.0, 1.0) gl.Enable(gl.CULL_FACE) gl.Viewport(0, 0, 800, 600) } func glfwInitWindowContext() { if err := glfw.Init(); err != nil { fmt.Fprintf(os.Stderr, "glfw_Init: %s\n", err) glfw.Terminate() } glfw.OpenWindowHint(glfw.FsaaSamples, 1) glfw.OpenWindowHint(glfw.WindowNoResize, 1) if err := glfw.OpenWindow(width, height, 0, 0, 0, 0, 32, 0, glfw.Windowed); err != nil { fmt.Fprintf(os.Stderr, "glfw_Window: %s\n", err) glfw.CloseWindow() } glfw.SetSwapInterval(1) glfw.SetWindowTitle("Title") } func drawScene() { for glfw.WindowParam(glfw.Opened) == 1 { gl.Clear(gl.COLOR_BUFFER_BIT) vertexShaderSrc := `#version 120 attribute vec2 coord2d; void main(void) { gl_Position = vec4(coord2d, 0.0, 1.0); }` vertexShader := gl.CreateShader(gl.VERTEX_SHADER) vertexShader.Source(vertexShaderSrc) vertexShader.Compile() fragmentShaderSrc := `#version 120 void main(void) { gl_FragColor[0] = 0.0; gl_FragColor[1] = 0.0; gl_FragColor[2] = 1.0; }` fragmentShader := gl.CreateShader(gl.FRAGMENT_SHADER) fragmentShader.Source(fragmentShaderSrc) fragmentShader.Compile() program := gl.CreateProgram() program.AttachShader(vertexShader) program.AttachShader(fragmentShader) program.Link() attribute_coord2d := program.GetAttribLocation("coord2d") program.Use() //attribute_coord2d.AttribPointer(size, typ, normalized, stride, pointer) attribute_coord2d.EnableArray() attribute_coord2d.AttribPointer(0, 3, false, 0, &(points[0])) //gl.DrawArrays(gl.TRIANGLES, 0, len(points)) gl.DrawArrays(gl.TRIANGLES, 0, 3) glfw.SwapBuffers() inputHandler() time.Sleep(100 * time.Millisecond) } } func inputHandler() { glfw.Enable(glfw.StickyKeys) if glfw.Key(glfw.KeyEsc) == glfw.KeyPress { //gl.DeleteBuffers(2, &uiVBO[0]) glfw.Terminate() } if glfw.Key(glfw.KeyF2) == glfw.KeyPress { glfw.SetWindowTitle("Title2") fmt.Println("Changed to 'Title2'") fmt.Println(len(points)) } if glfw.Key(glfw.KeyF1) == glfw.KeyPress { glfw.SetWindowTitle("Title1") fmt.Println("Changed to 'Title1'") } } func main() { runtime.LockOSThread() glfwInitWindowContext() initScene() drawScene() } And after that: panic: runtime error: invalid memory address or nil pointer dereference [signal 0xb code=0x1 addr=0x0 pc=0x41bc6f74] goroutine 1 [syscall]: github.com/go-gl/gl._Cfunc_glDrawArrays(0x4, 0x7f8500000003) /tmp/go-build463568685/github.com/go-gl/gl/_obj/_cgo_defun.c:610 +0x2f github.com/go-gl/gl.DrawArrays(0x4, 0x3, 0x0, 0x45bd70) /tmp/go-build463568685/github.com/go-gl/gl/_obj/gl.cgo1.go:1922 +0x33 main.drawScene() /home/klink/Dev/Go/gogl/gopher/exper.go:85 +0x1e6 main.main() /home/klink/Dev/Go/gogl/gopher/exper.go:116 +0x27 goroutine 2 [syscall]: created by runtime.main /build/buildd/golang-1/src/pkg/runtime/proc.c:221 exit status 2

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• What's your take on the programming language Go?

  - by fbrereto

  I've just been told about a new programming language, Go, developed at Google by such notables as Ken Thompson and Rob Pike. Does anyone have any experience with it so far? What are your thoughts about how viable small- and large-scale applications could be developed with it? Relevant links (thanks to Lance Roberts; feel free to update these as necessary): Ars-Technica PC World Google Open Source Blog Tech Talk Video Go Mailing List

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• Sizeof struct in GO

  - by Homer J. Simpson

  I'm having a look at Go, which looks quite promising. I am trying to figure out how to get the size of a go struct, for example something like type Coord3d struct { X, Y, Z int64 } Of course I know that it's 24 bytes, but I'd like to know it programmatically.. Do you have any ideas how to do this ?

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• Implementing ICMP ping in Go

  - by marketer

  Is it possible to implement an ICMP ping in Go? The alternative is to fork a 'ping' process, but I'd rather write it in Go.

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• What do you use to write Go

  - by LantisGaius

  I know its a bit too early, but I've been trying out Go (Google's Programming Language) and its kindof annoying to write code in gedit. So, my question: What do you use to experiment with Go?

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• Writing a Python extension in Go (golang)

  - by tehwalrus

  I currently use Cython to link C and Python, and get speedup in slow bits of python code. However, I'd like to use go routines to implement a really slow (and very parallelizable) bit of code, but it must be callable from python. (I've already seen this question) I'm (sort of) happy to go via C (or Cython) to set up data structures etc if necessary, but avoiding this extra layer would be good from a bug fix/avoidance point of view. What is the simplest way to do this without having to reinvent any wheels?

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• Trouble with go tour crawler exercise

  - by David Mason

  I'm going through the go tour and I feel like I have a pretty good understanding of the language except for concurrency. On slide 71 there is an exercise that asks the reader to parallelize a web crawler (and to make it not cover repeats but I haven't gotten there yet.) Here is what I have so far: func Crawl(url string, depth int, fetcher Fetcher, ch chan string) { if depth <= 0 { return } body, urls, err := fetcher.Fetch(url) if err != nil { ch <- fmt.Sprintln(err) return } ch <- fmt.Sprintf("found: %s %q\n", url, body) for _, u := range urls { go Crawl(u, depth-1, fetcher, ch) } } func main() { ch := make(chan string, 100) go Crawl("http://golang.org/", 4, fetcher, ch) for i := range ch { fmt.Println(i) } } The issue I have is where to put the close(ch) call. If I put a defer close(ch) somewhere in the Crawl method, then I end up writing to a closed channel in one of the spawned goroutines, since the method will finish execution before the spawned goroutines do. If I omit the call to close(ch), as is shown in my example code, the program deadlocks after all the goroutines finish executing but the main thread is still waiting on the channel in the for loop since the channel was never closed.

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• Cassandra datastore client in Go language

  - by Rafal Sobota

  Is it possible to write client for Cassandra datastore in Go language?

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