Re: :tangle header argument not picked up in #+PROPERTY line or :PROPERTIES: block

[Joost Kremers]

On Sun, Mar 29 2020, Berry, Charles via General discussions about 
Org-mode. wrote:
> What we really need is an ECM rather than snippets of code.

Yes, my apologies. It seems that having more than one `header-arg` 
line doesn't work properly. The following works:

```
* Header 1
:PROPERTIES:
:header-args:python: :tangle out1.py
:header-args:python: :session py1 :results function
:END:
#+begin_src python
a=1
b=2
c=a+b
return c
#+end_src

#+RESULTS:
: 3
```

But if I swap the two `header-args` lines, tangling stops working 
and at the same time evaluating the code block doesn't give any 
output at all:

```
* Header 1
:PROPERTIES:
:header-args:python: :session py1 :results function
:header-args:python: :tangle out1.py
:END:
#+begin_src python
a=1
b=2
c=a+b
return c
#+end_src

#+RESULTS:
```

With a `#+PROPERTY` line, I can't make it work at all:

```
#+PROPERTY: header-args:python :tangle out.py
#+PROPERTY: header-args:python :results function

* Header 1
#+begin_src python
a=1
b=2
c=a+b
return c
#+end_src

#+RESULTS:
: 3
```

Evaluating the code block works, but tangling doesn't. Reversing 
the order of the `#+PROPERTY` lines has no effect in this case.

Looks like a bug, right?

--
Joost Kremers
Life has its moments