X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=week3.mdwn;h=39e472bf9a644c1bdac774790ed134f26ab7cf31;hp=e8a86e90bbc180f69d98d3af58680b40e2edf143;hb=12830f839dda3c46101812c38f5cb6d3926aa623;hpb=71bfc3a4fcf9ae9eddc1854bce2ff6d5f6869644;ds=sidebyside diff --git a/week3.mdwn b/week3.mdwn index e8a86e90..39e472bf 100644 --- a/week3.mdwn +++ b/week3.mdwn @@ -1,3 +1,12 @@ +[[!toc]] + +##More on evaluation strategies## + +Here are notes on [[evaluation order]] that make the choice of which +lambda to reduce next the selection of a route through a network of +links. + + ##Computing the length of a list## How could we compute the length of a list? Without worrying yet about what lambda-calculus implementation we're using for the list, the basic idea would be to define this recursively: @@ -415,7 +424,7 @@ to *the tail* of the list we were evaluating its application to at the previous ##Fixed-point Combinators Are a Bit Intoxicating## -![tatoo](/y-combinator.jpg) +![tatoo](/y-combinator-fixed.jpg) There's a tendency for people to say "Y-combinator" to refer to fixed-point combinators generally. We'll probably fall into that usage ourselves. Speaking correctly, though, the Y-combinator is only one of many fixed-point combinators.