X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=week1.mdwn;h=cacb73fc61c4d49d4b4afa2cf2c4df05d533447e;hp=f449ed49e8663878d519af2e55ddea82fd44603a;hb=9a4224ba2c49f246262dd164b7a9102c3ad64fd5;hpb=c3468a4b473b3cff1028e1c3d652719595d32fd3 diff --git a/week1.mdwn b/week1.mdwn index f449ed49..cacb73fc 100644 --- a/week1.mdwn +++ b/week1.mdwn @@ -57,18 +57,7 @@ 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. - -Examples of expressions: - - x - (y x) - (x x) - (\x y) - (\x x) - (\x (\y x)) - (x (\x x)) - ((\x (x x)) (\x (x x))) +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. 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: