How to get the content of a code block by its name?

How to get the content of a code block by its name?

[Rodrigo Morales]

* The question

Let's suppose I have this simple code block in a buffer (let's say
=A=)

#+NAME: five-numbers
#+begin_src bash
echo foo
seq 1 5
echo bar
#+end_src

How can I get the content of the code block with name =five-numbers=
as an string from any point in buffer =A=?

* Additional information

I'm asking this because I would like to have a function which would
help me insert a code block in the =:prologue= header argument of
another code block.

#+begin_src bash :prologue (get-code-block-as-string "five-numbers")
echo a
#+end_src

-- 
Greetings,
Rodrigo Morales.

IRC: rdrg109 (freenode)

Re: How to get the content of a code block by its name?

[Kyle Meyer]

Rodrigo Morales writes:

> * The question
>
> Let's suppose I have this simple code block in a buffer (let's say
> =A=)
>
> #+NAME: five-numbers
> #+begin_src bash
> echo foo
> seq 1 5
> echo bar
> #+end_src
>
> How can I get the content of the code block with name =five-numbers=
> as an string from any point in buffer =A=?

This came up somewhat recently, and there were a couple of suggestions:
https://orgmode.org/list/CA+pajW+jViTPE2cwTZ=tHVZyHjrT000-BB6JK2ntE4P9UFBmpQ@mail.gmail.com/T/#u

Re: How to get the content of a code block by its name?

[Rodrigo Morales]

Kyle Meyer <kyle@kyleam.com> writes:

> This came up somewhat recently, and there were a couple of suggestions:
> https://orgmode.org/list/CA+pajW+jViTPE2cwTZ=tHVZyHjrT000-BB6JK2ntE4P9UFBmpQ@mail.gmail.com/T/#u

Thanks for the information! That was really helpful. I retrieved some
information from that post and wrote the following function.I would
really appreciate if someone could give me some feedback on this
function.

#+begin_src elisp
(defun org-babel-get-block-as-string (name)
  "Get the content of a code block with name NAME as an
string. This function also considers the code blocks stored in
`org-babel-library-of-babel'."
  (interactive)
  (catch 'found
    ;; Let's first search the code block in the current buffer.
    (let ((position (org-babel-find-named-block name)) content)
      (if position
	  (progn
	    (setq content
		  (save-excursion
		    (goto-char position)
		    ;; This function uses `org-babel-expand-src-block'
		    ;; instead of `org-edit-src-code' so that the
		    ;; value of the header arguments :prologue and the
		    ;; :epilogue are included as the content of the
		    ;; code block.
		    (org-babel-expand-src-block)))
	    (throw 'found content))))
    ;; If the code block doesn't exist in the current buffer, then
    ;; let's search in `org-babel-library-of-babel'.
    (let ((library-block-data (alist-get (intern name) org-babel-library-of-babel)) content)
      (if library-block-data
	  (progn
	    (setq content (nth 1 library-block-data))
	    (throw 'found content))))
    ; If the code block is not found, then an error is shown. Throwing
    ; an error is important since this makes code blocks which uses
    ; this function as the :epilogue and :prologue don't be evaluated
    ; in the scenario that a code block is not found.
    (error (format "The code block with name \"%s\" was not found" name))))
#+end_src

* Minimal example

Below, there is an example that shows how to use this function.

We can use =printf= as it follows

#+NAME: test-printf
#+begin_src bash
printf "%s\n" "printf-foo"
printf "%s\n" "printf-bar"
#+end_src

#+RESULTS: test-printf
#+begin_example
printf-foo
printf-bar
#+end_example

We can use =echo= as it follows

#+NAME: test-echo
#+begin_src bash
echo echo-foo
echo echo-bar
#+end_src

#+RESULTS: test-echo
#+begin_example
echo-foo
echo-bar
#+end_example

We can use both of them as it follows

#+HEADER: :prologue (org-babel-get-block-as-string "test-printf")
#+HEADER: :epilogue (org-babel-get-block-as-string "test-echo")
#+begin_src bash
echo a	
#+end_src

#+RESULTS:
#+begin_example
printf-foo
printf-bar
a
echo-foo
echo-bar
#+end_example


-- 
Greetings,
Rodrigo Morales.

IRC: rdrg109 (freenode)