X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=topics%2Fweek1_advanced_notes.mdwn;h=2137d114a5afeb4fdb27dcdce05fc194fcc8997b;hp=640becb74b861c7130ce14bc7b2a60c3e01595e2;hb=a363ca06fde540cfd6c0abb062c88611f1a84c45;hpb=e1fdd8196ae3bea9817524b6951d299497c0ec7a diff --git a/topics/week1_advanced_notes.mdwn b/topics/week1_advanced_notes.mdwn index 640becb7..2137d114 100644 --- a/topics/week1_advanced_notes.mdwn +++ b/topics/week1_advanced_notes.mdwn @@ -130,6 +130,7 @@ Both of these strategies work. But they are a bit inefficient. I said you didn't end + ### $ Syntax ### Haskell has a useful bit of syntax that we will adopt. They use `$` as an infix operator that has the same kind of effect as Russell & Whitehead's period. It is semantically inert, and only affects grouping. It enables you to avoid some parentheses in lots of situations. For example, if you want to check that a sequence `xs` is not empty, you'd express that like this: