In org-mode, when tangling/exporting source code blocks, how do I remove the line padding that appears before/after each block? - org-mode

Question

I have this in my org-mode file:
This is how we define a function:
#+BEGIN_SRC ruby :tangle hello.rb
def hello
puts 'Hello world!'
end
#+END_SRC
And this is how we call it:
#+BEGIN_SRC ruby :tangle hello.rb
hello
#+END_SRC
However, when I use org-babel-tangle it appears like this in the file:
[blank line]
def hello
puts 'Hello world!'
end
[blank line]
hello
[blank line]
How do I get it so all the blank lines do not appear?

Answer 1

The way to suppress the extra blank lines that appear around the exported source code is to use the header argument padline. Set it to no and it will not add blank lines.
With the above example, you would do this:
This is how we define a function:
#+BEGIN_SRC ruby :padline no :tangle hello.rb
def hello
puts 'Hello world!'
end
#+END_SRC
And this is how we call it:
#+BEGIN_SRC ruby :padline no :tangle hello.rb
hello
#+END_SRC
If you are within a heading, you can use the #+PROPERTY setting to set this up for all source code blocks within the buffer or for just the sub-heading with the following:
* My Section
:PROPERTIES:
:header-args: :padline no :tangle hello.rb
:END