From: Jim Pryor Date: Sun, 21 Nov 2010 20:54:49 +0000 (-0500) Subject: week9 tweak X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=commitdiff_plain;h=40b5ff7bf5c1f0fe0843ca938af8ced1ec5c9976;hp=677d5bbd54d54101e2855598db2aaae0d9ed6bad week9 tweak Signed-off-by: Jim Pryor --- diff --git a/week9.mdwn b/week9.mdwn index 568fc812..2b804839 100644 --- a/week9.mdwn +++ b/week9.mdwn @@ -291,7 +291,11 @@ Now we're going to relativize our interpretations not only to the assignment fun > \[[expression]]g s = (value, s') -For expressions we already know how to interpret, `s'` will usually just be `s`. One exception is complex expressions like `let var = expr1 in expr2`. Part of interpreting this will be to interpret the sub-expression `expr1`, and we have to allow that in doing that, the store may have already been updated. We want to use that possibly updated store when interpreting `expr2`. Like this: +For expressions we already know how to interpret, expect `s'` to just be `s`. +An exception is complex expressions like `let var = expr1 in expr2`. Part of +interpreting this will be to interpret the sub-expression `expr1`, and we have +to allow that in doing that, the store may have already been updated. We want +to use that possibly updated store when interpreting `expr2`. Like this: let rec eval expression g s = match expression with