Questions tagged [mapping]
34 questions
17
votes
4 answers
Is there an idiomatic way of reading each line in a buffer to process it line by line?
In Python I'd do the following to process a file line by line:
with open(infile) as f:
for line in f:
process(line)
Trying to look up how to do the same in elisp (with buffers instead of files), I found no obvious way.
(What I want to…
The Unfun Cat
- 2,413
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9
votes
3 answers
How to apply mapcar to a function with multiple arguments
I have packages variables that have list of github users and package names.
(defvar packages '('("auto-complete" . "auto-complete")
("defunkt" . "markdown-mode")))
I want to git clone if the file is not exist yet.
(defun…
ironsand
- 423
- 3
- 14
6
votes
2 answers
Emacs - Understand elisp syntax (mapcar '1+ '(2 4 6))
I saw this example code:
(mapcar '1+ '(2 4 6))
⇒ (3 5 7)
But I do not understand '1+ here. it will apply a function to a list but this style obviously not like a function. If means add, the function should be +, what does '1+ mean?
beetlej
- 1,098
- 1
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1
vote
1 answer
How to include an index in a list generated by mapcar?
This statements generates a list of (list filename buf),
How could this be written to include an index as well?
eg: (list index filename buf) where the index would be a counter, starting at zero, increment 1 for each item.
(mapcar
(lambda (buf)…
ideasman42
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