Question

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 -> Integer
add a b = a+b

-- Test my function 
add 2 3

If I load that little script in Hugs98, I get the following error:

Syntax error in declaration (unexpected `}', possibly due to bad layout)

If I remove the last line, load the script and then type in “add 2 3” in the hugs interpreter, it works just fine.

So the question is: How can I put calls of my functions in the same script as the function definition? I just want to load the script and be able to check if it does what I expect it to…I don’t want to type them in manually all the time.

Answer 1

Make a top level definition:

add :: Integer -> Integer -> Integer
add a b = a + b

test1 = add 2 3

Then call test1 in your Hugs session.