Difference between revisions of "VTLUUG:2016-03-24"

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imported>Echarlie
(Lambda Calculus for Babies: Retarded Babies)
imported>Echarlie
(Beta reduction)
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Meat of Lambda calculus.
 
Meat of Lambda calculus.
  
Ex:
+
===Examples===
  
 
<pre>
 
<pre>
  (ƛx.x)2
+
                            Currying example:
(ƛ[x:=2x])
+
  (ƛx.x)2                   (ƛabc.cba)zz(ƛwv.w)
     2
+
(ƛ[x:=2x])         (ƛa.(ƛb.(ƛc.cba)))(z)z(ƛw.(ƛv.w)))  The first function
 +
     2                   (ƛa.(ƛb.zba)z(ƛw.(ƛv.w)        Only applies the first z
  
  
 
(ƛz.zz)(ƛy.yy)
 
(ƛz.zz)(ƛy.yy)
 
(ƛ[z:=(ƛ
 
(ƛ[z:=(ƛ
 +
 +
  
 
</pre>
 
</pre>

Revision as of 01:14, 25 March 2016

Our seventh meeting of the 2016 Spring semester, and Officer Elections

Date, Time, and Location

Announcements

Curriculum du jour

  • Officer Elections
    • This is a consequence of new club registration policies.

Results

  • President
    • Jacob Melton
  • VP of not IT
    • Marcus Wanners
  • Secretary/Treasurer
    • John Volk

Talks

  • ackthet is giving the talk: Lambda Calculus for Babies. Retarded Babies.
    • First in ackthet's 10-part talk on Xmonad, starting from the basics of haskell

Hacking

Lambda Calculus for Babies: Retarded Babies

Lambda Calculus forms the fundamentals of functional programming. If it can be described as a function, it can be described in the lambda calculus and consequently written in Haskell

Alpha equivalence

  • Variable name doesn't matter

Beta reduction

Meat of Lambda calculus.

Examples

                            Currying example:
 (ƛx.x)2                   (ƛabc.cba)zz(ƛwv.w)
(ƛ[x:=2x])          (ƛa.(ƛb.(ƛc.cba)))(z)z(ƛw.(ƛv.w)))  The first function
    2                    (ƛa.(ƛb.zba)z(ƛw.(ƛv.w)        Only applies the first z


(ƛz.zz)(ƛy.yy)
(ƛ[z:=(ƛ



Currying