Is there a fopen-like function in elisp
I am aware of insert-file-contents idiom:
(defun read-lines (filePath)
(with-temp-buffer
(insert-file-contents filePath)
(split-string (buffer-string) "n" t)))
But is there a more natural way to read a file line by line without reading the whole file at once? I am looking for fopen/fread-like functionality.
emacs elisp
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
add a comment |
I am aware of insert-file-contents idiom:
(defun read-lines (filePath)
(with-temp-buffer
(insert-file-contents filePath)
(split-string (buffer-string) "n" t)))
But is there a more natural way to read a file line by line without reading the whole file at once? I am looking for fopen/fread-like functionality.
emacs elisp
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
I'll just note that you can pass BEG and END parameters toinsert-file-contentsto insert only part of the file. Not what you're asking for, but worth pointing out.
– phils
Oct 16 '18 at 23:22
add a comment |
I am aware of insert-file-contents idiom:
(defun read-lines (filePath)
(with-temp-buffer
(insert-file-contents filePath)
(split-string (buffer-string) "n" t)))
But is there a more natural way to read a file line by line without reading the whole file at once? I am looking for fopen/fread-like functionality.
emacs elisp
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
I am aware of insert-file-contents idiom:
(defun read-lines (filePath)
(with-temp-buffer
(insert-file-contents filePath)
(split-string (buffer-string) "n" t)))
But is there a more natural way to read a file line by line without reading the whole file at once? I am looking for fopen/fread-like functionality.
emacs elisp
emacs elisp
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
edited Nov 16 '18 at 9:45
tripleee
94.2k13132186
94.2k13132186
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
asked Oct 14 '18 at 13:11
ivaigultivaigult
3,12021841
3,12021841
I'll just note that you can pass BEG and END parameters toinsert-file-contentsto insert only part of the file. Not what you're asking for, but worth pointing out.
– phils
Oct 16 '18 at 23:22
add a comment |
I'll just note that you can pass BEG and END parameters toinsert-file-contentsto insert only part of the file. Not what you're asking for, but worth pointing out.
– phils
Oct 16 '18 at 23:22
I'll just note that you can pass BEG and END parameters to
insert-file-contents to insert only part of the file. Not what you're asking for, but worth pointing out.– phils
Oct 16 '18 at 23:22
I'll just note that you can pass BEG and END parameters to
insert-file-contents to insert only part of the file. Not what you're asking for, but worth pointing out.– phils
Oct 16 '18 at 23:22
add a comment |
1 Answer
1
active
oldest
votes
I think that the natural way of working with files in emacs is loading the file in buffer, After that you can process it line by line. take also a look to this answer in emacs stackexchange and this blog post from ergoemacs
like for example this:
ELISP> (find-file "foo.txt")
#<buffer foo.txt>
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (current-line-contents))
(forward-line 1))
In order not to get the properties, you can use the function thing-at point:
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1))
"line 1
"
"line 2
"
"line 3
"
"line 4
"
nil
if you need to work with temporary bufferss for speed reasons try this:
(with-temp-buffer
(insert-file-contents "./foo.txt")
(while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1)))
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
I think that the natural way of working with files in emacs is loading the file in buffer, After that you can process it line by line. take also a look to this answer in emacs stackexchange and this blog post from ergoemacs
like for example this:
ELISP> (find-file "foo.txt")
#<buffer foo.txt>
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (current-line-contents))
(forward-line 1))
In order not to get the properties, you can use the function thing-at point:
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1))
"line 1
"
"line 2
"
"line 3
"
"line 4
"
nil
if you need to work with temporary bufferss for speed reasons try this:
(with-temp-buffer
(insert-file-contents "./foo.txt")
(while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1)))
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
add a comment |
I think that the natural way of working with files in emacs is loading the file in buffer, After that you can process it line by line. take also a look to this answer in emacs stackexchange and this blog post from ergoemacs
like for example this:
ELISP> (find-file "foo.txt")
#<buffer foo.txt>
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (current-line-contents))
(forward-line 1))
In order not to get the properties, you can use the function thing-at point:
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1))
"line 1
"
"line 2
"
"line 3
"
"line 4
"
nil
if you need to work with temporary bufferss for speed reasons try this:
(with-temp-buffer
(insert-file-contents "./foo.txt")
(while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1)))
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
add a comment |
I think that the natural way of working with files in emacs is loading the file in buffer, After that you can process it line by line. take also a look to this answer in emacs stackexchange and this blog post from ergoemacs
like for example this:
ELISP> (find-file "foo.txt")
#<buffer foo.txt>
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (current-line-contents))
(forward-line 1))
In order not to get the properties, you can use the function thing-at point:
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1))
"line 1
"
"line 2
"
"line 3
"
"line 4
"
nil
if you need to work with temporary bufferss for speed reasons try this:
(with-temp-buffer
(insert-file-contents "./foo.txt")
(while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1)))
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
I think that the natural way of working with files in emacs is loading the file in buffer, After that you can process it line by line. take also a look to this answer in emacs stackexchange and this blog post from ergoemacs
like for example this:
ELISP> (find-file "foo.txt")
#<buffer foo.txt>
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (current-line-contents))
(forward-line 1))
In order not to get the properties, you can use the function thing-at point:
ELISP> (goto-char 1)
1 (#o1, #x1, ?C-a)
ELISP> (while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1))
"line 1
"
"line 2
"
"line 3
"
"line 4
"
nil
if you need to work with temporary bufferss for speed reasons try this:
(with-temp-buffer
(insert-file-contents "./foo.txt")
(while (not (eobp))
(print (thing-at-point 'line t))
(forward-line 1)))
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
edited Nov 16 '18 at 10:07
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
answered Nov 15 '18 at 19:31
anquegianquegi
6,38432845
6,38432845
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
add a comment |
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
My problem with copying a file to a buffer is that it is horribly slow. It could be like five minutes for non-minified JSON file. Especially, it is slow when the file is a binary file or doesn't contain line endings.
– ivaigult
Nov 16 '18 at 9:58
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
I updated the question maybe it shloud work for you, now in terms of speed
– anquegi
Nov 16 '18 at 10:04
add a comment |
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I'll just note that you can pass BEG and END parameters to
insert-file-contentsto insert only part of the file. Not what you're asking for, but worth pointing out.– phils
Oct 16 '18 at 23:22