From 7f092b37815e93a96ad581b8dd5b16fc67bb4bfc Mon Sep 17 00:00:00 2001 From: barker Date: Mon, 20 Sep 2010 20:46:26 -0400 Subject: [PATCH] --- lambda_evaluator.mdwn | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/lambda_evaluator.mdwn b/lambda_evaluator.mdwn index 16eace75..552ac686 100644 --- a/lambda_evaluator.mdwn +++ b/lambda_evaluator.mdwn @@ -13,10 +13,21 @@ In this toy system, `let`s should only be used at the beginning of a file. If w let true = (\x (\y x)) in let false = (\x (\y y)) in - ((true true) false) + ((true yes) no) -the result is `true`. +the result is `yes`. Things to watch out for: the expression after the equal sign must have balanced parentheses, +and the "in" is obligatory. The system will still produce a result, but it won't make much sense. + +*Comments*: anything following a semicolon to the end of the line is ignored. +Blank lines are fine. + +Under the hood +--------------- + +The interpreter is written in JavaScript (which is not closely related to Java), and runs inside your browser. +So if you decide to reduce a term that does not terminate (such as `((\x (x x)) (\x (x x)))`), it will be your +browser that stops responding, not the wiki server. + +You can inspect the code [here](http://lambda.jimpryor.net/code/lambda.js). Suggestions for improvements welcome. -*Comments*: -[more soon] -- 2.11.0