causes the
function to abort.  `:defer` can be used to avoid that: >
	func Filter(text) abort
	  call writefile(a:text, 'Tempfile')
	  defer delete('Tempfile')
	  defer delete('Outfile')
	  call system('filter < Tempfile > Outfile')
	  call Handle('Outfile')
	endfunc

Note that deleting "Outfile" is scheduled before calling `system()`, since it
can be created even when `system()` fails.

The deferred functions are called in reverse order, the last one added is
executed first.  A useless example: >
	func Useless() abort
	  for s in range(3)
	    defer execute('echomsg "number ' .. s .. '"')
	  endfor
	endfunc

Now `:messages` shows:
	number 2
	number 1
	number 0

Any return value of the deferred function is discarded.  The function cannot
be followed by anything, such as "->func" or ".member".  Currently
`:defer GetArg()->TheFunc()` does not work, it may work in a later version.

Errors are reported but do not cause aborting execution of deferred functions
or altering execution outside of deferred functions.

No range is accepted.  The function can be a partial with extra arguments, but
not with a dictionary. *E1300*

==============================================================================

4. Automatically loading functions ~
							*autoload-functions*
When using many or large functions, it's possible to automatically define them
only when they are used.  There are two methods: with an autocommand and with
the "autoload" directory in 'runtimepath'.


Using an autocommand ~

This is introduced in the user manual, section |41.14|.

The autocommand is useful if you have a plugin that is a long Vim script file.
You can define the autocommand and quickly quit the script with `:finish`.
That makes Vim startup faster.  The autocommand should then load the same file
again, setting a variable to skip the `:finish` command.

Use the FuncUndefined autocommand event with a pattern that matches the
function(s) to be defined.  Example: >

	:au FuncUndefined BufNet* source ~/vim/bufnetfuncs.vim

The file "~/vim/bufnetfuncs.vim" should then define functions that start with
"BufNet".  Also see |FuncUndefined|.


Using an autoload script ~
							*autoload* *E746*
This is introduced