X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=exercises%2F_assignment4.mdwn;h=589932e293b25c0ea181109adc4606eb8a5d0dcc;hp=7c01388b14d9f32351a82c63d942ebf61ab926e6;hb=18249c1fe8e2c49440f26029b2a8e1416f9a15ed;hpb=e14a493f3df7e2e501265518ffa3a6b70a88ca1c diff --git a/exercises/_assignment4.mdwn b/exercises/_assignment4.mdwn index 7c01388b..589932e2 100644 --- a/exercises/_assignment4.mdwn +++ b/exercises/_assignment4.mdwn @@ -18,7 +18,7 @@ points.) 4. Assume that `Ψ` is some fixed point combinator; we're not telling you which one. (You can just write `Psi` in your homework if you don't know how to generate the symbol `Ψ`.) Prove that `Ψ Ψ` is a fixed point of itself, that is, that `Ψ Ψ <~~> Ψ Ψ (Ψ Ψ)`. - Y(YY) --> YY(Y(YY)); YY(YY) --> YY(Y(YY)) --> + ## Writing recursive functions ##