User:Echo Nolan/Reactive Banana: Straight to the Point
So I'm writing this tutorial as a means of teaching myself FRP and reactive-banana. It'll probably be full of errors and bad advice, use it at your own risk.
All the tutorials on FRP I've read start with a long boring theory section. This is an instant gratification article. For starters, imagine a man attempting to sharpen a banana into a deadly weapon. See? You're gratified already! Now for a boring bit:
Go install mplayer: <code-bash>apt-get install mplayer # Or equivalent</code-bash>
Get the git repository associated with this tutorial: <code-bash>git clone https://github.com/enolan/rbsttp.git </code-bash>
Install reactive-banana <code-bash> cabal install reactive-banana</code-bash>
Cd into the git repo and open rbsttp.hs in GHCi:
<pre-bash> cd rbsttp ghci rbsttp.hs </pre-bash>
Now, we can make some beepy noises. Try these:
<pre-haskell> playNote C2 playNote C6 sequence_ . intersperse (threadDelay 1000000) $ map playNote [C2 ..] </pre-haskell>
Play with the value passed to threadDelay a bit for some more interesting noises. It's expresssed in microseconds.
<pre-haskell> sequence_ . intersperse (threadDelay 500000) $ map playNote [C2 ..] sequence_ . intersperse (threadDelay 250000) $ map playNote [C2 ..] sequence_ . intersperse (threadDelay 125000) $ map playNote [C2 ..] sequence_ . intersperse (threadDelay 62500) $ map playNote [C2 ..] </pre-haskell>