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> It's also an ideal language for expressing complex ideas, such as [...] finding the shortest route on a map So, I googled "Dijkstra's Algorithm in Lisp" and

> It's also an ideal language for expressing complex ideas, such as [...] finding the shortest route on a map So, I googled "Dijkstra's Algorithm in Lisp" and got this: http://richardsherriff.com/?p=233 http://richardsherriff.com/?p=233 Now, I'm no lisp expert, so I can't judge whether the author of this code actually knows what they're doing, but I know for sure that in an imperative language the implementation of the algorithm is much more concise and understandable. I have concluded from my observations that claims of Lisp being "easier", "ideal for learning fundamental programming concepts" and "more expressive" are exaggerated.

lispm 10y ago
Congratulations, you have found the most ugly Lisp code ever. > so I can't judge whether the author of this code actually knows what they're doing Not really. He can't even format the code. For example from that blog post: (defun return_highers_helper (list element result) (cond ((null list) result) ((equalp (first element) (first (first list))) (cond ((< (rest element) (rest(car list))) (return_highers_helper (cdr list) element (cons (car list) result))) (t (return_highers_helper (cdr list) element result)) )) (t (return_highers_helper (cdr list) element result)) )) This would be written usually as: (defun %return-highers (element list) (remove-if-not (lambda (item) (and (equalp (car element) (car item)) (< (cdr element) (cdr item)))) list))
WillPostForFood 10y ago
There are better comparisons here. The Lisp version is pretty nice compared to most of the imperative versions: http://rosettacode.org/wiki/Dijkstra%27s_algorithm http://rosettacode.org/wiki/Dijkstra%27s_algorithm
Volt 10y ago
>in an imperative language Lisp is capable of imperative programming.
- pjmlp 10y ago
  I would say multi-paradigm instead.
e12e 10y ago
You might want to look at something like: https://github.com/gwkkwg/cl-graph/blob/master/dev/graph-algorithms.lisp#L59 https://github.com/gwkkwg/cl-graph/blob/master/dev/graph-alg... or perhaps: https://planet.racket-lang.org/package-source/jaymccarthy/dijkstra.plt/1/2/dijkstra.ss https://planet.racket-lang.org/package-source/jaymccarthy/di... I was a little surprised to not find any direct graph algorithms at rosetta code[1], but for showing off somewhat similar code, this might be of interest: http://rosettacode.org/wiki/Longest_common_subsequence#Common_Lisp http://rosettacode.org/wiki/Longest_common_subsequence#Commo... I don't really think common lisp is a great beginning language, compared to, say, python or ruby - although Racket Scheme is pretty nice. I did for example come across this introduction to A * that uses Python for the code examples: http://www.redblobgames.com/pathfinding/a-star/introduction.html http://www.redblobgames.com/pathfinding/a-star/introduction.... As for introduction to new programmers, Racket's tutorial is kind of nice, jumping right in to do some simple graphics with an embedded DSL: https://docs.racket-lang.org/quick/ https://docs.racket-lang.org/quick/ [1] WillPostForFood obviously out-searched me here, finding: http://rosettacode.org/wiki/Dijkstra%27s_algorithm http://rosettacode.org/wiki/Dijkstra%27s_algorithm Not sure how I managed to not find it - perhaps trusting search rather than trying to use the site-index would've helped...
cscurmudgeon 10y ago
1. Find bad possibly code written in a language (by possibly a starting student). 2. Use it to invalidate any arbitrary claim X about the language. 3. Profit?

lispm 10y ago

Congratulations, you have found the most ugly Lisp code ever. > so I can't judge whether the author of this code actually knows what they're doing Not really. He can't even format the code. For example from that blog post: (defun return_highers_helper (list element result) (cond ((null list) result) ((equalp (first element) (first (first list))) (cond ((< (rest element) (rest(car list))) (return_highers_helper (cdr list) element (cons (car list) result))) (t (return_highers_helper (cdr list) element result)) )) (t (return_highers_helper (cdr list) element result)) )) This would be written usually as: (defun %return-highers (element list) (remove-if-not (lambda (item) (and (equalp (car element) (car item)) (< (cdr element) (cdr item)))) list))

WillPostForFood 10y ago

There are better comparisons here. The Lisp version is pretty nice compared to most of the imperative versions: http://rosettacode.org/wiki/Dijkstra%27s_algorithm http://rosettacode.org/wiki/Dijkstra%27s_algorithm

Volt 10y ago

>in an imperative language Lisp is capable of imperative programming.

pjmlp 10y ago
I would say multi-paradigm instead.

e12e 10y ago

You might want to look at something like: https://github.com/gwkkwg/cl-graph/blob/master/dev/graph-algorithms.lisp#L59 https://github.com/gwkkwg/cl-graph/blob/master/dev/graph-alg... or perhaps: https://planet.racket-lang.org/package-source/jaymccarthy/dijkstra.plt/1/2/dijkstra.ss https://planet.racket-lang.org/package-source/jaymccarthy/di... I was a little surprised to not find any direct graph algorithms at rosetta code[1], but for showing off somewhat similar code, this might be of interest: http://rosettacode.org/wiki/Longest_common_subsequence#Common_Lisp http://rosettacode.org/wiki/Longest_common_subsequence#Commo... I don't really think common lisp is a great beginning language, compared to, say, python or ruby - although Racket Scheme is pretty nice. I did for example come across this introduction to A * that uses Python for the code examples: http://www.redblobgames.com/pathfinding/a-star/introduction.html http://www.redblobgames.com/pathfinding/a-star/introduction.... As for introduction to new programmers, Racket's tutorial is kind of nice, jumping right in to do some simple graphics with an embedded DSL: https://docs.racket-lang.org/quick/ https://docs.racket-lang.org/quick/ [1] WillPostForFood obviously out-searched me here, finding: http://rosettacode.org/wiki/Dijkstra%27s_algorithm http://rosettacode.org/wiki/Dijkstra%27s_algorithm Not sure how I managed to not find it - perhaps trusting search rather than trying to use the site-index would've helped...

cscurmudgeon 10y ago

1. Find bad possibly code written in a language (by possibly a starting student). 2. Use it to invalidate any arbitrary claim X about the language. 3. Profit?