From 199d99a994e1801b4ef884bda4cce38470ef6fa1 Mon Sep 17 00:00:00 2001 From: Jim Date: Sun, 1 Feb 2015 13:03:37 -0500 Subject: [PATCH] add summary to week1 --- topics/week1.mdwn | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/topics/week1.mdwn b/topics/week1.mdwn index f195b8d9..430cc5dd 100644 --- a/topics/week1.mdwn +++ b/topics/week1.mdwn @@ -614,3 +614,28 @@ You have all the materials you need now to do this week's [[assignment|assignmen There are also some [[advanced notes|week1 advanced notes]] extending this week's material. +### Summary ### + +Here is the hierarcy of **values** that we've talked about so far. + +* Multivalues +* Singular values, including: + * Atoms, including: + * Numbers: these are among the **literals** + * Symbolic atoms: these are also among the **literals**, and include: + * Booleans (or truth-values) + * Functions: these are not literals, but instead have to be generated by evaluating complex expressions + * Containers, including: + * the literals `[]` and `{}` + * Non-empty sequences + * Non-empty sets + * Tuples proper and other containers, to be introduced later + +We've also talked about a variety of **expressions** in our language, that evaluate down to various values (if their evaluation doesn't "crash" or otherwise go awry). These include: + +* All of the literal atoms and literal containers +* Variables +* Various complex expressions, built using `&` or λ or `let` or `letrec` or `case` + +The special syntaxes `[10, 20, 30]` are just shorthand for the more offical syntax using `&` and `[]`, and likewise for `{10, 20, 30}`. The `if ... then ... else ...` syntax is just shorthand for a `case`-construction using the literal patterns `'true` and `'false`. + -- 2.11.0