MeEd

MeEd

Title: Effective Haskell (Page 31)

@RebeccaSkinner

At the bottom of page 31 when let is added to the example greeting I cannot get the example to work. I’ve tried rechecking spacing inside the example, made sure I copied the example correctly and put in hours trying to get the example to work. I get different errors every time I try to run it in ghci.

First Post!

RebeccaSkinner

RebeccaSkinner

Author of Effective Haskell

Hey, sorry you’re having a problem! Here’s a working version of the example you can copy and paste:

module Main where

makeGreeting salutation person =
  let messageWithTrailingSpace = salutation <> " "
  in messageWithTrailingSpace <> person

extendedGreeting person =
  let hello = makeGreeting "Hello" person
      goodDay = makeGreeting "I hope you have a nice afternoon" person
      goodBye = makeGreeting "see you later" person
  in hello <> "\n" <> goodDay <> "\n" <> goodBye

main = print $ extendedGreeting "George"

If you can paste your code and the output of the errors I’d be happy to help you spot what’s going on!

Where Next?

Popular Pragmatic Bookshelf topics Top

simonpeter
When I try the command to create a pair of migration files I get an error. user=&gt; (create-migration "guestbook") Execution error (Ill...
New
mikecargal
Title: Hands-On Rust (Chap 8 (Adding a Heads Up Display) It looks like ​.with_simple_console_no_bg​(SCREEN_WIDTH*2, SCREEN_HEIGHT*2...
New
brian-m-ops
#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
New
oaklandgit
Hi, I completed chapter 6 but am getting the following error when running: thread 'main' panicked at 'Failed to load texture: IoError(O...
New
akraut
The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error. lib/pento_web/live/product_l...
New
Henrai
Hi, I’m working on the Chapter 8 of the book. After I add add the point_offset, I’m still able to see acne: In the image above, I re...
New
tkhobbes
After some hassle, I was able to finally run bin/setup, now I have started the rails server but I get this error message right when I vis...
New
EdBorn
Title: Agile Web Development with Rails 7: (page 70) I am running windows 11 pro with rails 7.0.3 and ruby 3.1.2p20 (2022-04-12 revision...
New
Keton
When running the program in chapter 8, “Implementing Combat”, the printout Health before attack was never printed so I assumed something ...
New
dachristenson
@mfazio23 Android Studio will not accept anything I do when trying to use the Transformations class, as described on pp. 140-141. Googl...
New

Other popular topics Top

PragmaticBookshelf
Ruby, Io, Prolog, Scala, Erlang, Clojure, Haskell. With Seven Languages in Seven Weeks, by Bruce A. Tate, you’ll go beyond the syntax—and...
New
dasdom
No chair. I have a standing desk. This post was split into a dedicated thread from our thread about chairs :slight_smile:
New
AstonJ
SpaceVim seems to be gaining in features and popularity and I just wondered how it compares with SpaceMacs in 2020 - anyone have any thou...
New
New
AstonJ
You might be thinking we should just ask who’s not using VSCode :joy: however there are some new additions in the space that might give V...
New
Exadra37
I am asking for any distro that only has the bare-bones to be able to get a shell in the server and then just install the packages as we ...
New
mafinar
Crystal recently reached version 1. I had been following it for awhile but never got to really learn it. Most languages I picked up out o...
New
PragmaticBookshelf
Author Spotlight Rebecca Skinner @RebeccaSkinner Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...
New
First poster: AstonJ
Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...
New
Margaret
Ask Me Anything with Mark Volkmann @mvolkmann On February 24 and 25, we are giving you a chance to ask questions of PragProg author M...
New

Sub Categories: