Re: emacs takes exhorbitantly long to read long, one-line files.

[Dmitry Antipov]

On 05/19/2013 07:52 AM, Randy Yates wrote:

> I have a file (a matlab .m file of a vector of data) that is all on
> one line and about 2 MB:
>
>    http://www.digitalsignallabs.com/dspin.m
>
> emacs takes a very long time (6 minutes?) to read this in, and
> practically becomes unusable in the mean time.

In this particular case, Emacs just thinks that your file is an Objective-C
source code, and tries to fontify it accordingly. This attempt implies a lot
of buffer scans, and substantial amount of them may be slow for the very
long lines. Since I suspect that you don't want to edit this as Obj-C, try:

emacs --eval "(setq auto-mode-alist (cons '(\"\\.m\" . fundamental-mode) 
auto-mode-alist))" dspin.m

Dmitry