Difference between revisions of "User:Echo Nolan/Reactive Banana: Straight to the Point"

From HaskellWiki
Jump to: navigation, search
(New page: == Introduction == So I'm writing this tutorial as a means of teaching myself FRP and reactive-banana. It'll probably of errors and bad advice, use it at your own risk. All the tutorials...)
 
(Introduction)
Line 1: Line 1:
 
== Introduction ==
 
== Introduction ==
   
So I'm writing this tutorial as a means of teaching myself FRP and reactive-banana. It'll probably of errors and bad advice, use it at your own risk.
+
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:
 
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>
+
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>
 
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>
  +
  +
== Musical interlude ==
  +
  +
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>

Revision as of 17:37, 18 September 2012

Introduction

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>

Musical interlude

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>