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From: Rolf Ade <rolf@pointsman.de>
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Subject: Re: How to test if the current line contains only white-spache?
Date: Sun, 15 Nov 2015 20:18:55 +0100
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Barry Margolin <barmar@alum.mit.edu> writes:
>  Rolf Ade <rolf@pointsman.de> wrote:
>
>> For some random minor elisp code I need to know, if the current line
>> contains only white-space characters[1].
>> 
>> I came up with this somewhat convoluted code:
>> 
>> (beginning-of-line)
>> (skip-chars-forward " \t")
>> (let ((text-start (current-column)))
>>   (end-of-line)
>>   (if (= text-start (current-column))
>>       t
>>     nil)
>> 
>> (and that is, obviously, without saving point position and wrapping
>> into and a defun and maybe other bells and whistles).
>> 
>> I wonder, what much simpler and more elegant solution I'm missing.
>
> (save-excursion
>   (beginning-of-line)
>   (looking-at "[ \t]*$"))

Works fine and is much simpler. Thanks.