An editor is a program that lets us write longer programs than we can
write on the >>> prompt. Then we can save the programs to files and
run them as many times as we want without writing them again.
When programmers say "editor" they don't mean programs like Microsoft Word or LibreOffice/OpenOffice Writer. These programs are for writing text documents, not for programming. Programming editors don't support things like bigger font sizes for titles or underlining bits of text, but instead they have features that are actually useful for programming, like automatically displaying different things with different colors.
If you are on Windows or Mac OSX you have probably noticed that your Python came with an editor called IDLE. We are not going to use it because it's lacking some important features, and most experienced programmers (including me) don't use it or recommend it.
The choice of an editor is a very personal thing. There are many editors, and most programmers have a favorite editor that they use for everything and recommend to everyone.
If you aren't sure about which editor you should use, I recommend Porcupine. It's a simple editor I wrote in Python; it lets you edit files and it doesn't have too many other featues. Install it with these instructions, and then learn to use it by writing the classic Hello World program. Then you can skip the rest of this chapter.
Note that most other editors come with settings that are not suitable for writing Python code. TODO: add a link to the old editor setup tutorial here.
Most of these editors lack some important features, they have so many features that confuse people or they aren't free. You can use these editors if you like them, but these editors are BAD for getting started with programming:
- PyCharm
- IDLE
- Emacs
- Gedit
- Nano
- NetBeans
- Notepad
- Pluma
- Spyder
- Vim
- Wingware
This list doesn't contain all bad editors, but these are editors that people often try to use. If you know a bad editor and you think I should mention it here, please let me know.
So far we have used the >>> prompt for everything. But now we also
have an editor that lets us write longer programs. So why not just
always use the editor?
The >>> prompt is meant to be used for experimenting with things. For
example, if you want to know what "hello" + 123 does, just open the
prompt and run it.
If you want to write something once and then run it many times, write the code to a file. For example, if you want to make a program that asks the user to enter a word and then echoes it back, write a program that does that in a file and run it as many times as you want to.
Note that if you write something like 'hello' to the >>> prompt it
echoes it back, but if you make a file that contains nothing but a
'hello' it won't do anything when you run it. You need to use
print('hello') instead when your code is in a file.