From 6a256ca9562cd593b68e312c3c4de5146272db04 Mon Sep 17 00:00:00 2001 From: Marshall Lochbaum Date: Fri, 8 Jan 2021 21:47:53 -0500 Subject: Span hasn't been introduced yet! --- tutorial/combinator.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tutorial') diff --git a/tutorial/combinator.md b/tutorial/combinator.md index 4450e68e..c4f523d7 100644 --- a/tutorial/combinator.md +++ b/tutorial/combinator.md @@ -195,7 +195,7 @@ Here are the diagrams for Before and After: as promised, they're not symmetrical DrawComp ≍"⊸⟜" --> -What about the one-argument case? The structure of application is exactly the same, except that there's only one argument available, so it's used in both input positions. If I describe it that way, it sounds like lazy design, but the ability to use one argument in two ways makes the one-argument versions of Before and After even more useful than the two-argument ones. For example, consider the function `y = x×(1-x)`, which gives a parabola that's equal to 0 at 0 and 1, and peaks between them when x is 0.5. Remembering that Span (`¬`) is defined so that `¬x` is `1-x`, we can write this function as either `¬⊸×` or `×⟜¬`. +What about the one-argument case? The structure of application is exactly the same, except that there's only one argument available, so it's used in both input positions. If I describe it that way, it sounds like lazy design, but the ability to use one argument in two ways makes the one-argument versions of Before and After even more useful than the two-argument ones. For example, consider the function `y = x×(1-x)`, which gives a parabola that's equal to 0 at 0 and 1, and peaks between them when x is 0.5. The function Not (`¬`, which we'll discuss in a later tutorial) is defined so that `¬x` is `1-x`, which conveniently allows us to write this function as either `¬⊸×` or `×⟜¬`. ¬⊸× 0.5 -- cgit v1.2.3