Rasmus Lerchedahl Petersen: Untied Fixed Points (hands-on)

Abstract:

Functional programming languages make heavy use of recursive functions.

When we define a recursive function, we are asking the compiler to compute a fixed point. However, the language is actually powerful enough for us to define a fixed point combinator and thus compute the fixed point ourselves.

Dismantling the definition of recursive functions in this way is, I hope, both fun and illustrative as it offers some interesting possibilities.

By separating the function definition from the fixed point computation, it is possible to insert a stage of modifications in between the two, altering the produced function in surprising ways.

Some optimisations, for instance, can be added in this stage, thus not cluttering the function definition itself. This allows code which is both clear and fast.

Bring your laptop and look forward to destructing your favourite recursive functions.

Speaker: Rasmus Lerchedahl Petersen (https://www.meetup.com/MoedegruppeFunktionelleKoebenhavnere/members/185683993/)

After completing a degree in theoretical computer science from the IT University, Rasmus spent 4 years in London building static analysers.

He then spent 4 years in Cambridge studying DNA computing, and is now with a small start-up in Stockholm.

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We have set up a collaboration with Prosa, who generously offered to provide a location for our regular meetups. Please see Prosa's Calendar for more details: Prosa Calendar (https://www.prosa.dk/kalender/hele-kalenderen/)

The ADA meeting room fits about 25 people and if we need more space, we can use the canteen (PASCAL), which has a capacity of at most 50 (fire regulation).

Regards,

Ramón and Joakim