Add approaches for Leap #643
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This is really cool @ceddlyburge, thank you for taking the leap to add approaches (pun intended :D )
There is some cleaning to do in the code.
| Using a case expression with a `Tuple` is idiomatic in Elm, but Tuple's have a maximum of 3 values, so can't be used for anything larger than this. | ||
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| Strings and arrays can hold more values and can also be used with case expressions, which are useful in many circumstances. | ||
| Using an array with a case expression and recursion is especially common. |
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Did you mean an Array here, or a List?
| divisbleBy number = | ||
| modBy number year == 0 | ||
| in | ||
| if divisbleBy(400) then |
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The brackets are strange here
| modBy number year == 0 | ||
| in | ||
| if divisbleBy(400) then | ||
| return True |
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return?
Haha, the copy/paste is strong with this one :)
Where did you take the code from? Do they have the divisble typo as well?
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Ha! I did copy paste this, but it was from an Elm solution on exercism, so I assumed that it passed the tests and worked!
| else if divisbleBy(100) then | ||
| return False | ||
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| else if divisbleBy(4) then |
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I'm not sure that if something then True else False is ever better than something, especially in Elm where there is no truthiness.
Co-authored-by: Jie <[email protected]>
Co-authored-by: Jie <[email protected]>
Co-authored-by: Jie <[email protected]>
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Thanks for the review Jeremie, I missed some pretty obvious things there! Hopefully they are all fixed now ... |
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| This approach uses exactly two tests to determine whether a year is a leap year. | ||
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| The first test is for divisibility by 100. |
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This doesn't match the actual code, since we start by checking 400.
From the description, the code would probably be (untested)
isLeapYear : Int -> Bool
isLeapYear year =
let
divisibleBy number =
modBy number year == 0
in
if divisibleBy 100 then
divisibleBy 400
else
divisibleBy 4which only has one if statement. If you don't want to change the description, I would consider changing to this code (after double checking that it passes the tests).
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It does pass the tests, I'll use it ...
| "Truth tables" | ||
| [esoteric-approach] | ||
| https://exercism.org/tracks/elm/exercises/leap/solutions/edgerunner | ||
| "An esoteric solution to leap, using recursion, a list and a case expression" |
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That really is esoteric 😆
Add approaches for the leap exercise (which is being used as part of the 48 i 24 challenge, starting 16 January)
https://forum.exercism.org/t/48in24-exercise-01-16-leap/8964
Fixes #644.