flatmap.io

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Prerequisites

You need to install the following software:

• Stack for Haskell
  • yesod web framework
  • hlint to improve your Haskell
  • hindent to make your Haskell pretty
• Docker to run mongo
  • MongoDB to store data

Haskell Setup

1. If you haven't already, install Stack
   • On POSIX systems, this is usually curl -sSL https://get.haskellstack.org/ | sh
2. Install the yesod command line tool: stack install yesod-bin --install-ghc
3. Build libraries: stack build

If you have trouble, refer to the Yesod Quickstart guide for additional detail.

Hlint

stack install hlint

Hindent

stack install hindent

How to run

Expose MongoDB on localhost with default port 27017

Start a development server with:

stack exec -- yesod devel

As your code changes, your site will be automatically recompiled and redeployed to http://localhost:3000.

Tests

stack test --flag h-map:library-only --flag h-map:dev

(Because yesod devel passes the library-only and dev flags, matching those flags means you don't need to recompile between tests and development, and it disables optimization to speed up your test compile times).

Documentation

• Read the Yesod Book online for free
• Check Stackage for documentation on the packages in your LTS Haskell version, or search it using Hoogle. Tip: Your LTS version is in your stack.yaml file.
• For local documentation, use:
  • stack haddock --open to generate Haddock documentation for your dependencies, and open that documentation in a browser
  • stack hoogle <function, module or type signature> to generate a Hoogle database and search for your query
• The Yesod cookbook has sample code for various needs

Getting Help

• Ask questions on Stack Overflow, using the Yesod or Haskell tags
• Ask the Yesod Google Group
• There are several chatrooms you can ask for help:
  • For IRC, try Freenode#yesod and Freenode#haskell
  • Functional Programming Slack, in the #haskell, #haskell-beginners, or #yesod channels.