Re:Not Lisp again (2009)
by sigjuice on Wednesday May 03, 2017 @11:28AM
(#14256516)
Exactly. IMHO, this is quite similar to Python indentation rules, except it is up to writers of Lisp code to be disciplined enough to maintain the proper indentation.
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Hmm, my editor does it for me.
Wait, even Lisp does that for me, because it has a built-in source code pretty printer:
Call the pretty printer to format this mess:
CL-USER 41 > (let ((*print-case* :downcase))
(pprint '(defun add-text-padding
(str &key padding newline)
"Add padding to text STR. Every line except for the first one, will be
prefixed with PADDING spaces. If NEWLINE is non-NIL, newline character will
be prepended to the text making it start on the next line with padding
applied to every single line."
(let ((str (if newline (concatenate 'string (string #\Newline) str) str)))
(with-output-to-string (s) (map 'string (lambda (x) (princ x s) (when (char= x #\Newline)
(dotimes (i padding) (princ #\Space s)))) str))))
))
It prints wonderfully formatted and indented code: (defun add-text-padding (str &key padding newline)
"Add padding to text STR. Every line except for the first one, will be
prefixed with PADDING spaces. If NEWLINE is non-NIL, newline character will
be prepended to the text making it start on the next line with padding
applied to every single line."
(let ((str
(if newline
(concatenate 'string (string #\Newline) str)
str)))
(with-output-to-string (s)
(map 'string
(lambda (x)
(princ x s)
(when (char= x #\Newline)
(dotimes (i padding) (princ #\Space s))))
str))))
Now one would only need to fix this beginner level code.No. Our editors auto-indent the code for us. This is one of the reasons Lisp syntax is better than python. Python syntax does not have enough information to auto-indent so it really is up to the programmer. Not so with Lisp.
I hate when I code python and refactor stuff, moving stuff around and such, that I cant just copy/clip around and then do a final 'indent all my work correctly' like I can in a language like lisp.
I am kind of developing a grudge against whitespace sensitive languages. Not because it forces the programmer to indent properly, but because it disables my editors abilities to do it for me.
Actually, Python has the equivalent of open-parens: the colon. What it doesn't have is close-parens, but if you use emacs then it will outdent on PASS and RETURN statements. In my personal coding style I always put PASS statements at the end of block so my code auto-indents properly. Hard-core Pythonistas hate this, but I really don't care what they think.