andre

andre

Effective Haskell:Chapter 13 (B9 - PDF version) - infinite loop when running the ClassyArchiver code

Refer to pages 508-511

I get an infinite loop when running the original parseArchive function, after adding a variable called "archiveDef, which codifies the example given on p.491.


archiveDef :: Text
archiveDef = Text.unlines $
  [ "archive \"example.archive\":"
  , ""
  , "import \"./extras/example1.txt\""
  , ""
  , "new-file \"inline-example.txt\":"
  , "     this is some text"
  , "     it can have newlines"
  , "     but it needs to be indented"
  , ""
  , "import \"./extras/example2.txt\""
  ]

λ> runArchiver archiveDef parseArchive

I’ve changed the parseArchive function by removing “parseBlock”.
I commented out the original line and added the modification under it.


parseArchive :: Archiver Archive
parseArchive = do
    expectText "archive"
    dropSpaces
    archiveName <- quotedString
    expectText ":\n"
    -- files <- parseBlock parseArchiveStatements
    files <- parseArchiveStatements               -- CHANGE HERE
    pure $ Archive archiveName files

The infinite loop disappears when using this modified version.

Where Next?

Popular Pragmatic Bookshelf topics Top

abtin
page 20: … protoc command… I had to additionally run the following go get commands in order to be able to compile protobuf code using go...
New
jon
Some minor things in the paper edition that says “3 2020” on the title page verso, not mentioned in the book’s errata online: p. 186 But...
New
jamis
The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...
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
raul
Hi Travis! Thank you for the cool book! :slight_smile: I made a list of issues and thought I could post them chapter by chapter. I’m rev...
New
New
redconfetti
Docker-Machine became part of the Docker Toolbox, which was deprecated in 2020, long after Docker Desktop supported Docker Engine nativel...
New
gorkaio
root_layout: {PentoWeb.LayoutView, :root}, This results in the following following error: no “root” html template defined for PentoWeb...
New
davetron5000
Hello faithful readers! If you have tried to follow along in the book, you are asked to start up the dev environment via dx/build and ar...
New
roadbike
From page 13: On Python 3.7, you can install the libraries with pip by running these commands inside a Python venv using Visual Studio ...
New

Other popular topics Top

AstonJ
Thanks to @foxtrottwist’s and @Tomas’s posts in this thread: Poll: Which code editor do you use? I bought Onivim! :nerd_face: https://on...
New
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
PragmaticBookshelf
Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...
New
DevotionGeo
I have always used antique keyboards like Cherry MX 1800 or Cherry MX 8100 and almost always have modified the switches in some way, like...
New
PragmaticBookshelf
Author Spotlight: Peter Ullrich @PJUllrich Data is at the core of every business, but it is useless if nobody can access and analyze ...
New
First poster: bot
zig/http.zig at 7cf2cbb33ef34c1d211135f56d30fe23b6cacd42 · ziglang/zig. General-purpose programming language and toolchain for maintaini...
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
AstonJ
If you’re getting errors like this: psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
New
AnfaengerAlex
Hello, I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...
New

Sub Categories: