How do you fold functions automatically?

Question

Is there a way to make Vim fold functions based on the syntax of a function declaration?

For example having vim turn a function like this:

def foobar(foo,bar):
  if foo > bar:
    print "foo"
  elif foo < bar:
    print "bar"
  elif foo == bar:
    print "foobar"

Into this:

+----- 7 lines: def foobar(foo,bar): -------------------------------------------------------------

Is there some set of commands or a function I can put into my .vimrc file use to accomplish this?

Answer 1

Given that your example is in Python, which relies on correct indentation of code blocks it is enough to base folding on that:

:set foldmethod=indent

For more information on the varieties of folding available see :help foldmethod

Answer 2

Sure:

set foldmethod=syntax

You can then use zc to close a fold, zo to open one, or za to toggle.

Unfortunately, Vim doesn't include folding information for Python by default, which you appear to be using. You could use one of many external resources, however.

Answer 3

This is my vimrc command to automatically fold a function pressing F4 when my cursor is placed on the function definition:

" fold whole function
nmap <silent> <F4> /{<CR>zfa}