[JAVA] Make a bookmarklet in Python

This is the first post I made a bookmarklet that works with code written in Python using Brython The second half is just code golf

What is Brython

http://qiita.com/ryo_grid/items/5e34220ed48f4580126d This was very helpful.

There is demand

(Maybe) No

I wrote it for the time being

bookmarklet

javascript:
(function() {
  var py = document.createElement('script');
  py.type = 'text/python';
  py.src = 'https://example/script.py';
  document.body.appendChild(py);
  var br = document.createElement('script');
  br.src = 'https://example/brython.js';
  br.onload = function() {
    brython();
  };
  document.body.appendChild(br);
})();

/script.py

from browser import alert

alert("Hello World!")

The mechanism is simple, just before </ body>

<script type="text/python" src="https://example/script.py"></script>
<script src="https://example/brython.js"></script>

Is just adding After loading brython.js, callbrython ()using the onload attribute to run the text / python script in the page.

Cross-domain problem

Brython uses Ajax to load any external scripts Therefore, there is a fatal problem that bookmarklets do not work except on the server page where the script is placed. So I solved it by adding ʻAccess-Control-Allow-Origin: *` to the HTTP header

shorten

It's a bookmarklet, so it should be shorter (?)

Omit the declaration and change the variable name to one character

Also put the document in a variable

javascript:
(function(d,p,b) {
  p = d.createElement('script');
  p.type = 'text/python';
  p.src = 'https://example/script.py';
  d.body.appendChild(p);
  b = d.createElement('script');
  b.src = 'https://example/brython.js';
  b.onload = function() {
    brython();
  };
  d.body.appendChild(b);
})(document);

Recursion

Call with ʻarguments.callee` because there is no function name (If you give a function name, a space will be inserted and it is inappropriate as a bookmarklet) Use ternary operator without if statement

javascript:
(function d(d,u,c,e) {
  e = d.createElement('script');
  e.src = u + (c ? 'brython.js' : 'script.py');
  c ? (arguments.callee(d,u), e.onload = function() {
    brython();
  }) : (e.type = 'text/python');
  d.body.appendChild(e);
})(document,'https://example/',1);

Remove spaces, line breaks

javascript:(function d(d,u,c,e) {e=d.createElement('script');e.src=u+(c?'brython.js':'script.py');c?(arguments.callee(d,u),e.onload=function(){brython();}):(e.type='text/python');d.body.appendChild(e);})(document,'https://example/',1);

330 characters => 235 characters I think it's still a long time, but my technology seems to be the limit

It's over, have a good Python life!