ob-go enables Org-Babel support for evaluating go code. It was
created based on the usage of ob-C. The go code is compiled and run
via the go run command. If a main function isn’t present, by
default the code is wrapped in a simple main func. If :package
option isn’t set and no package is declared in the code, then the
main package is declared.
#+begin_src go :imports "fmt"
fmt.Println("Hello, 世界")
#+end_src
:
#+results: : Hello, 世界
In addition to the normal header arguments for Babel, below are some some headers specific to go.
:args- Command line arguments to pass to the executable compiled from the code block. To pass more than one argument, use a list.
:flags- Flags to pass to the
go runcommand. These are the flags that you would pass togo build. :main- If set to
no, inhibits the auto wrapping of themainfunction call. Default: yes :imports- Shorthand for supplying imports to the app. This should be
used when you’re letting the application handle the
mainfunction. To supply more, use a list. :package- Set the package of the file. Requires :main no. If
not set, and code doesn’t have a explicit package, then
mainpackage is declared. Set tonilby using:package 'discard :var- `ob-go’ also supports Babel variables with some limitations. See
`ob-go’ for more information about some of the limitations using
:var.
#+begin_src go :imports '("fmt" "time")
fmt.Println("Current Time:", time.Now())
#+end_src
:
#+RESULTS: : Current Time: 2012-04-29 11:47:36.933733 -0700 PDT
#+begin_src go // A concurrent prime sieve package main
:
import "fmt"
:
// Send the sequence 2, 3, 4, ... to channel 'ch'.
func Generate(ch chan<- int) {
for i := 2; ; i++ {
ch <- i // Send 'i' to channel 'ch'.
}
}
:
// Copy the values from channel 'in' to channel 'out',
// removing those divisible by 'prime'.
func Filter(in <-chan int, out chan<- int, prime int) {
for {
i := <-in // Receive value from 'in'.
if i%prime != 0 {
out <- i // Send 'i' to 'out'.
}
}
}
:
// The prime sieve: Daisy-chain Filter processes.
func main() {
ch := make(chan int) // Create a new channel.
go Generate(ch) // Launch Generate goroutine.
for i := 0; i < 10; i++ {
prime := <-ch
fmt.Println(prime)
ch1 := make(chan int)
go Filter(ch, ch1, prime)
ch = ch1
}
}
#+end_src
:
#+RESULTS: #+begin_example 2 3 5 7 11 13 17 19 23 29 #+end_example
Tests can be executed by make test or invoking emacs directly with the command-line below:
# For Emacs earlier than 24, add -L /path/to/ert
emacs -Q --batch \
-L . \
-l ob-go.el \
-l test-ob-go.el \
--eval "(progn \
(setq org-confirm-babel-evaluate nil) \
(org-babel-do-load-languages \
'org-babel-load-languages '((emacs-lisp . t) \
(sh . t) \
(org . t) \
(go . t))))" \
-f ob-go-test-runall