Standard ML of New Jersey (SML/NJ)
SML/NJ is a popular implementation of the Standard ML programming language that was co-developed jointly by Bell Laboratories and Princeton University. It is released under a BSD like license.
References:
Questions tagged [smlnj]
866 questions
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How to use if-then-else in a recursive function
I am writing a function that will take a list of list and merge it into sorted pairs of list. For example [[1],[9],[8],[7],[4],[5],[6]] would return [[1,9],[7,8],[4,5],[6]]. This is my first attempt at SML. I keep getting this error: operator and…
R_86
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How to call two functions in a let..in.. in SML/NJ
I'm trying to call two separate functions within a function. One
function generates and presents a random List to a user and the other
function uses the random list and sorts it.
fun getNumber() = (
print "Please enter the number of integers:…
XXIV
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Extracting values from a function via matching
I'm working on an assignment and was given the following function:
fun label (lb,ub) =
let val s = callcc (fn k =>let fun branch c = if (c < ub)
then (pushCP (k,branch,c+1);c)
…
oihnkj
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Input / Output operations - ML
I am learning ML.
Can some one please help me out with basic input/output functions in ML??
I just want to read input from console and store it in a variable and use it in my ML program.
Please help. If you can point me towards some example for this…
JJunior
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composition of the functions
I need to write some function NTimesComposition(f:(int * int -> int), n:int) which receives some function f and integer n and after doing composition of f, n times, like this f(x,(f(x,f(x,y)))) <- (here for example n = 3) I began to write it on…
rookie
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SMLNJ - Function works by itself, but not within another function
I have this function:
addBinaryTreeNode((genRandomNumber(100), genRandomNumber(100), genRandomNumber(100)), tree, 1, [])
That returns a data type "binaryTree". It will compile when that is by itself, but when I have it in a…
EpicBlargh
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How can I maintain a counter when using map on a list?
This is for a class assignment.
I am to implement a function in ML evalxy poly x y where poly is an int list list that represents a polynomial. A term at position n in its inner list and position m in the outer list is the coefficient for x^n * y^m.…
Dr. McKay
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How to Implement LPT (Longest Processing Time) Scheduling Algorithm function in SML
Suppose that we have a list with the processing time of some tasks,like this [13,8,7,6,4,2,2,1]. we want to divide this list into two list by LPT Scheduling Algorithm.here is the algorithm procedure:
with a given Descending sorted list like above,at…
Saeed Mousazadeh
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SML: How to insert elements of a list into another list based on a value?
I have a list and a value, how can I insert elements of the list into a new list until sum of those elements won't exceed that value?
The question is how to return the aforementioned new list and initial list without elements of new list?
For…
Saeed Mousazadeh
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1 answer
How to pretty-print tree-like value step by step?
So I've got a datatype:
datatype ex = A of int | B of ex * ex;
and an example variable:
val x = (B (A 1, B (A 2, A 3)));
I want to be printing through it like this:
"(1, (2, 3))"
Any help would be appreciated! Thanks.
rshah
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How do I save an Standard ML program?
I am new to SML, but would like to get some experience with a strongly typed language. I've been looking at tutorials and I copied a simple factorial function:
fun Factorial n =
if n = 0 then 1
else n * Factorial (n-1);
However, I am not…
tpm900
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SML check if 2 items are in the same list
How do i check if 2 items are in the same list in sml? I tried changing a member function but i could not make it work.
val routeList1 = ["Princes Street", "Haymarket", "Craiglockhart", "Musselburgh", "Stoneybank"]
if want to check if both "Princes…
user7422388
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1 answer
Increase print depth for lists in SML/NJ
I'm using Emacs to write a simple function in sml of about 4 lines and when I try to call the function/evaluate it in the buffer it returns this with 3 dots at the end
val it = [1,2,2,2,2,2,2,2,2,2,2,2,...] : int list
What's the dots at the end? My…
Square-root
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How to keep elements in list through out the program in SML?
Suppose I have to update a list with each call to a function, such that, the previous element of the list are preserved.
Here is my attempt:
local
val all_list = [];
in
fun insert (x:int) : string = int2string (list_len( ((all_list@[x])) )…
ThunderWiring
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Why to replace `in` with `let` in sml?
I have a local block with few helper methods. After that, comes a main function (between the in and end block):
datatype color = BLACK | RED;
datatype 'a RBTree = Nil
| Br of (int * 'a * color) * 'a RBTree * 'a RBTree;
datatype Balance = RR…
ThunderWiring
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