Round a Float to a given number of decimal places

pi |> roundTo 2      --> 3.14
pi |> roundTo 0      --> 3
1234 |> roundTo -2   --> 1200

Convert a boolean string to a Bool, ignoring case

toBool "true"     --> Ok True
toBool "True"     --> Ok True
toBool "false"    --> Ok False
toBool "FALSE"    --> Ok False
toBool "blah"     --> Err "String argument must be 'true' or 'false' (case ignored)"

Given a list and a test value, returns True if the list contains a value equal to the test value.

Equivalent to List.member with the arguments flipped

Given a pair of values defining an interval and a test value, returns True if the test value falls within the interval, including its endpoints

Given a pair of values defining an interval and a test value, returns True if the test value falls strictly between the endpoints of the interval, such that a test value equal to one of the endpoints will return False

Given a 2-tuple of Maybe values, if both values are defined, return Just the 2-tuple of values; otherwise, return Nothing

maybe2Tuple (Just 1, Just 2)    --> Just (1,2)
maybe2Tuple (Just 1, Nothing)    --> Nothing

Given a 3-tuple of Maybe values, if all three values are defined, return Just the 3-tuple of values; otherwise, return Nothing

Given a 4-tuple of Maybe values, if all four values are defined, return Just the 4-tuple of values; otherwise, return Nothing

Given a list of Maybe values, if all values are defined, return Just the list of values; otherwise, return Nothing. When passed an empty list, returns Just an empty list.

maybeList [Just 1, Just 2]    --> Just [1,2]
maybeList [Just 1, Nothing]   --> Nothing
maybeList []                  --> Just []

Given a 2-tuple of Result values, if both values are Ok, return an Ok result containing the 2-tuple of values; otherwise, return an Err value.

result2Tuple "ERROR" (Ok 1, Ok 2)       --> Ok (1,2)
result2Tuple "ERROR" (Ok 1, Err "..")   --> Err "ERROR"

Given a 3-tuple of Result values, if all three values are Ok, return an Ok result containing the 3-tuple of values; otherwise, return an Err value.

Given a 4-tuple of Result values, if all three values are Ok, return an Ok result containing the 4-tuple of values; otherwise, return an Err value.

Given a list of Result values, if all values are Ok, return an Ok result containing the list of values; otherwise, return an error message. When passed an empty list, returns Ok [].

resultList "ERROR" [Ok 1, Ok 2]       --> Ok [1,2]
resultList "ERROR" [Ok 1, Err ".."]   --> Err "ERROR"
resultList []                         --> Ok []

Return a one-item list containing the argument

wrapList ("key", "value")


--> [ ("key", "value") ]

Get the value at the nth place of a list without converting the list to an array; returns Nothing if the list contains fewer than n + 1 items, or if n is negative

getNth 0 [1, 3, 9, 27]    --> Just 1
getNth 3 [1, 3, 9, 27]    --> Just 27
getNth 4 [1, 3, 9, 27]    --> Nothing
getNth -1 [1, 3, 9, 27]   --> Nothing

Returns the first two items in a list as a 2-tuple, or Nothing if the list contains fewer than two items

take2Tuple [1,2]    --> Just (1,2)
take2Tuple [1,2,3]  --> Just (1,2)
take2Tuple [1]      --> Nothing

Returns the first three items in a list as a 3-tuple, or Nothing if the list contains fewer than three items

Returns the first four items in a list as a 4-tuple, or Nothing if the list contains fewer than four items

Given a 2-tuple where both values are of the same type, return a list containing those values

Given a 3-tuple where all three values are of the same type, return a list containing those values

Given a 4-tuple where all four values are of the same type, return a list containing those values

Convert a 3-tuple of lists to a list of 3-tuples (see List.unzip)

Convert a 4-tuple of lists to a list of 4-tuples

Convert a 2-tuple of lists to a list of 2-tuples

zip ([0,17,1337], [True,False,True])


--> [(0, True), (17, False), (1337, True)]

Convert a 3-tuple of lists to a list of 3-tuples

Convert a 4-tuple of lists to a list of 4-tuples

Return the first value of a 3-tuple

Return the second value of a 3-tuple

Return the third value of a 3-tuple

Return the first value of a 4-tuple

Return the second value of a 4-tuple

Return the third value of a 4-tuple

Return the fourth value of a 4-tuple

Apply a function to both values in a 2-tuple and return the results as a 2-tuple

Apply a function to all 3 values in a 3-tuple and return the results as a 3-tuple

Apply a function to all 4 values in a 4-tuple and return the results as a 4-tuple

curry with 3 parameters

curry with 4 parameters

uncurry with 3 parameters

uncurry with 4 parameters

Given a tuple containing two functions and a value accepted by both functions, return a tuple containing the two results

Given a tuple containing three functions and a value accepted by all three functions, return a tuple containing the three results

Given a tuple containing four functions and a value accepted by all four functions, return a tuple containing the four results

Given a list containing any number of functions and a value accepted by every function in the list, return a list containing all of the results. Note that to use applyList, all of the results must be of the same type, which is not the case for the apply functions that return tuples.