For my studies I have to write the following function which gets the shortest route between two countries. I already have already written a function isRoute which checks if there is a connection be...

I just started with Haskell and tried to do write some tests first. Basically, I want to define some function and than call this function to check the behavior. add :: Integer -> Integer ->...

There are differences between Hugs, Yhc and GHCi? If there are differences, What are they?

I'm using Hugs interpreter and I want to execute the following code (by Haskell 2010 language report): let x = 1 z = x+y in z+1 Is it possible only creating a .hs file and loading? Can I do it b...

I was playing around with hugs today and got stuck at a very simple question: λ 1 1 :: (Num a, Num (a -> t)) => t What would that type be? I am having trouble to read this. And if it has ...

I'm reading Programming in Haskell book and testing provided examples in GHCi interpreter. It turns out, that there is a difference in Int type behavior in GHCi and Hugs interpreter. According to C...

I define five functions that seem to me like they should be equivalent (and, therefore, have the same type). But the inferred types are different. I put the following five lines in type-inference.h...

Given a list of points in a two dimensional space, you want to perform a function in Haskell to find the distance between the two closest points. example: Input: project [(1,5), (3,4), (2,8), (-1,2...

Patterns like this: front :: [a] -> a front (x:_) = x front _ = error "Empty list" seem to be common in Haskell, but I distinctively remember learning the following when I started learning Ha...

I'd like to write a Haskell program that uses GADTs interactively on a platform not supported by GHCi (namely, GNU/Linux on mipsel). The problem is, the construct that can be used to define a GADT ...

Hugs seems to have a problem with several non-enbraced !! in a partial application. While this works fine in GHCi: ([[0]]!!0!!)0 Hugs reports a syntax error for the ). Is this a bug in Hugs? ...

I'm working on parsing a CSV file into a CSV type which is a list of Record which is a list of Field, which are just Strings. After inserting a new row and then trying to access the csv I get the c...

I'm writing a C++ application that needs to interpret and evaluate haskell code. This code isn't known at compile time but given by the user. Is there a way to use a haskell compiler/interpreter (l...

Came across this while playing with Haskell and I'm stumped: Hugs> :type (\x -> x^2) \x -> x ^ 2 :: (Integral a, Num b) => b -> b What is a doing in there? How am I supposed to re...

Is there a Haskell interpreter that accepts type definitions or preferably all kinds of statements? I've already tried ghci and hugs and none of these does that. Is there some particular reason th...

f :: Integer -> Integer -> [Integer] f i n = n : f (i+2) (n+i) can someone explain to me what it does. i know it returns [0,1,4,9,16..] but i dont understand how and what n : f means