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# skovsgaard's solution

## to Anagram in the LFE Track

Published at Jul 13 2018 · 3 comments
Instructions
Test suite
Solution

Given a word and a list of possible anagrams, select the correct sublist.

Given `"listen"` and a list of candidates like `"enlists" "google" "inlets" "banana"` the program should return a list containing `"inlets"`.

For installation and learning resources, refer to the exercism help page.

To run the provided tests, you will need `make`. Open a terminal window and run the following from the exercise directory:

``````make test
``````

You should now be able to see the results of the test suite for the exercise.

## Source

Inspired by the Extreme Startup game https://github.com/rchatley/extreme_startup

## Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

### anagram-tests.lfe

``````(defmodule anagram-tests
(behaviour ltest-unit)
(export all))

(include-lib "ltest/include/ltest-macros.lfe")

(deftest no-matches
(is-equal () (anagram:find "diaper" '("hello" "world" "zombies" "pants"))))

(deftest detect-simple-anagram
(is-equal '("tan") (anagram:find "ant" '("tan" "stand" "at"))))

(deftest does-not-confuse-different-duplicates
(is-equal () (anagram:find "galea" '("eagle"))))

(deftest eliminate-angram-subsets
(is-equal () (anagram:find "good" '("dog" "goody"))))

(deftest detect-anagram
(is-equal
'("inlets")
(anagram:find "listen" '("enlists" "google" "inlets" "banana"))))

(deftest multiple-anagrams
(is-equal
'("gallery" "regally" "largely")
(anagram:find
"allergy"
'("gallery" "ballerina" "regally" "clergy" "largely" "leading"))))

(deftest case-insensitive-subject
(is-equal
'("carthorse")

(deftest case-insensitive-candidate
(is-equal
'("Carthorse")

(deftest does-not-detect-a-word-as-its-own-anagram
(is-equal
'("cron")
(anagram:find "corn" '("corn" "dark" "Corn" "rank" "CORN" "cron" "park"))))``````
``````(defmodule anagram
(export (find 2)))

(defun find (word possibilities)
(lists:filter
(lambda (x) (!= x '()))
(lc ((<- possibility possibilities))
(if (and
(== (lists:sort (string:to_lower word))
(lists:sort (string:to_lower possibility)))
(!= word (string:to_lower possibility)))
possibility
'()))))``````

There's no need to quote the empty list, ()

Consider "memoizing" (string:to_lower possibility)

Consider andalso instead of and to avoid unnecessary calculations

Consider folding the filter into the list comprehension I see what you're doing here.

skovsgaard
Solution Author

I'm not sure I understand andalso. Is it like short circuiting the and in Common Lisp? E.g. (and 'truthy 'values 'go 'here "Return something if they're all true")

Yeah, most notably, for example, this wouldn't throw: (andalso 'true (throw 'never))

but this would (and 'true (throw 'never))

Same goes for orelse vs or.

### What can you learn from this solution?

A huge amount can be learned from reading other peopleâ€™s code. This is why we wanted to give exercism users the option of making their solutions public.

Here are some questions to help you reflect on this solution and learn the most from it.

• What compromises have been made?