Re: Novice trouble with generator.el

[Davin Pearson]

On Tuesday, November 17, 2015 at 5:17:16 PM UTC+13, John Mastro wrote:
> > When I try to execute 
> > 
> > iter-defun iterator-of-directory-files (directory &optional full match 
> > nosort recurse)
> > 
> > it gives me the following error:
> > 
> > Assertion failed: lexical-binding
> > 
> > What gives?  Note that I am using Emacs 24.3.1.
> > 
> > Do I have to execute Emacs 25.x.y?
> 
> Put a comment like this as the very first line of the file:
> 
> ;;; lexical-binding: t
> 
> Lexical binding is optional in Emacs but generator.el requires it. 
> 
> -- 
> john

When I execute 

(iter-defun iterator-of-directory-files (directory &optional full match ...)

it says 

(void-function macroexp-parse-body)

I tried to install Emacs 25 using the following command:

apt-get install emacs25 

apt-get spits out the following error message:

E: Unable to locate package emacs25

How do I go about installing emacs25?