RosettaCodeData/Task/Roman-numerals-Decode/AppleScript/roman-numerals-decode-3.app...

111 lines
2.5 KiB
AppleScript

use framework "Foundation"
----------- INTEGER VALUE OF ROMAN NUMBER STRING ---------
-- fromRoman :: String -> Int
on fromRoman(s)
script subtractIfLower
on |λ|(l, rn)
set {r, n} to rn
if l r then -- Digit values that increase (L to R),
{l, n + l} -- (added)
else
{l, n - l} -- Digit values that go down: subtracted.
end if
end |λ|
end script
item 2 of foldr(subtractIfLower, {0, 0}, ¬
map(my charVal, characters of s))
end fromRoman
-- charVal :: Char -> Int
on charVal(C)
set v to lookup(toUpper(C), ¬
{I:1, |V|:5, X:10, |L|:50, C:100, D:500, M:1000})
if missing value is v then
0
else
v
end if
end charVal
--------------------------- TEST -------------------------
on run
map(fromRoman, ¬
{"MDCLXVI", "MCMXC", "MMVIII", "MMXVI", "MMXXI"})
--> {1666, 1990, 2008, 2016, 2021}
end run
-------------------- GENERIC FUNCTIONS -------------------
-- foldr :: (a -> b -> b) -> b -> [a] -> b
on foldr(f, startValue, xs)
tell mReturn(f)
set v to startValue
set lng to length of xs
repeat with I from lng to 1 by -1
set v to |λ|(item I of xs, v)
end repeat
return v
end tell
end foldr
-- lookup :: a -> Dict -> Maybe b
on lookup(k, dct)
-- Just the value of k in the dictionary,
-- or missing value if k is not found.
set ca to current application
set v to (ca's NSDictionary's dictionaryWithDictionary:dct)'s ¬
objectForKey:k
if missing value v then
item 1 of ((ca's NSArray's arrayWithObject:v) as list)
else
missing value
end if
end lookup
-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
-- The list obtained by applying f
-- to each element of xs.
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with I from 1 to lng
set end of lst to |λ|(item I of xs, I, xs)
end repeat
return lst
end tell
end map
-- Lift 2nd class handler function into 1st class
-- script wrapper
-- mReturn :: Handler -> Script
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
-- toUpper :: String -> String
on toUpper(str)
tell current application
((its (NSString's stringWithString:(str)))'s ¬
uppercaseStringWithLocale:¬
(its NSLocale's currentLocale())) as text
end tell
end toUpper