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

[Randy Yates]

Dmitry Antipov <address@hidden> writes:

> 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

I already had that in my init.el. I've also tried creating an empty
file and setting it to fundamental-mode. In both these cases the 
behavior is the same. 

I did notice that emacs is faster - but still unusably slow - when
toggle-truncate-lines is true.
-- 
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com