X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=week1.mdwn;h=897ef1f8ae37429e35509fd2cd0a8de984c12abc;hp=a5e697a5026751b9fb6b261f657cd2f91f69c99a;hb=3a08849b14cc00a2a279acd120f3835414ea1a82;hpb=aa82fa84a083b7b90862f5f4c368f07dd62ae717 diff --git a/week1.mdwn b/week1.mdwn index a5e697a5..897ef1f8 100644 --- a/week1.mdwn +++ b/week1.mdwn @@ -57,20 +57,20 @@ We'll tend to write (λa M) as just `(\a M)`, so we don't hav Application: (M N) -Some authors reserve the term "term" for just variables and abstracts. We won't *participate* in that convention; we'll probably just say "term" and "expression" indiscriminately for expressions of any of these three forms. +Some authors reserve the term "term" for just variables and abstracts. We won't participate in that convention; we'll probably just say "term" and "expression" indiscriminately for expressions of any of these three forms. Examples of expressions: x (y x) (x x) - (_x y) - (_x x) - (_x (_y x)) - (x (_x x)) - ((_x (x x)) (_x (x x))) + (\x y) + (\x x) + (\x (\y x)) + (x (\x x)) + ((\x (x x)) (\x (x x))) -The *lambda* calculus has an associated proof theory. For now, we can regard the proof theory as having just one rule, called the rule of **beta-reduction** or "beta-contraction". Suppose you have some expression of the form: +The lambda calculus has an associated proof theory. For now, we can regard the proof theory as having just one rule, called the rule of **beta-reduction** or "beta-contraction". Suppose you have some expression of the form: ((\a M) N)