From: S|ren von Leuscher
Subject: Genius help needed for Lambda Calc./Lisp questions.
Date: 
Message-ID: <1993Apr1.201653.17126@odin.diku.dk>
I am a novice in Lisp prog. and Lambda Calculus. Please could anybody
(perhaps a genius - I don't get the point with this stuff :))
out there help me with the following questions:

-----
1) How do I reduce this expression (Please explain step by step what
to do and why - capital l (L) stands for the greek lambda sign)

	(Lx.Ly.x (Lz.z u) (Lv.(v v) Lw.(w w)))

-----
2) What is the 'content' or meaning of Church-Rossers theorem?

-----

3) Define a List function (poly '(An An-1 ... A1 A0) X) that
calculates An X^n + An-1 X^n-1 + ... + A1 X + A0.

Example: 3*5^2 + 2*5^1 + 1

You should use accumulated parametres and use the following
formula for calculating the polynomium:

((...((An X + An-1)X + An-2)X + A1) X + A0)

-----
4) How do I test a Lisp program - formally!
Please not a quick explanation I need to understand this.

-------------------------------

I would be very happy if anybody could help me with theese questions
When (if) you have an answer please e-mail me personally not in the
newsgroup because I don't have the possibility to read news frequently.
Thanks in advance.

Mike.     (e-mail: ····@DIKU.DK)

From: Sean Philip Engelson
Subject: Re: Genius help needed for Lambda Calc./Lisp questions.
Date: 
Message-ID: <1pfpbfINNjpd@FRIDGE.AI.CS.YALE.EDU>
In article <·····················@odin.diku.dk>, ····@diku.dk (S|ren von Leuscher) writes:
|> 
|> I am a novice in Lisp prog. and Lambda Calculus. Please could anybody
|> (perhaps a genius - I don't get the point with this stuff :))
|> out there help me with the following questions:
|> -----
|> 1) How do I reduce this expression (Please explain step by step what
|> to do and why - capital l (L) stands for the greek lambda sign)
|> 
|> 	(Lx.Ly.x (Lz.z u) (Lv.(v v) Lw.(w w)))

Step 1: Decide to do your homework yourself
Step 2: Learn the material
Step 3: Do the reduction
Step 4: Write down the answer

|> 2) What is the 'content' or meaning of Church-Rossers theorem?

THEOREM: If you do your homework then you may learn something.

PROOF:	By inspection.

|> 3) Define a List function (poly '(An An-1 ... A1 A0) X) that
|> calculates An X^n + An-1 X^n-1 + ... + A1 X + A0.

(defun poly (x y)
  (if (did-my-homework 'me)
      (be-happy)
      (be-stupid)))

|> 4) How do I test a Lisp program - formally!

Exactly correct.  You test a Lisp program formally.  Very good!

|> I would be very happy if anybody could help me with theese questions

No problem.  Glad to help.

-- 
Sean Philip (Shlomo) Engelson		
Yale Department of Computer Science	
Box 2158 Yale Station			
New Haven, CT 06520			
From: Frank Yellin
Subject: Re: Genius help needed for Lambda Calc./Lisp questions.
Date: 
Message-ID: <FY.93Apr1140313@hardwick.lucid.com>
In article <·····················@odin.diku.dk> ····@diku.dk (S|ren von
Leuscher) writes: 

>   I am a novice in Lisp prog. and Lambda Calculus. Please could anybody
>   (perhaps a genius - I don't get the point with this stuff :))
>   out there help me with the following questions:
>
>   1) How do I reduce this expression . . . .
>   2) What is the 'content' or meaning of Church-Rossers theorem?
>   3) Define a List function (poly '(An An-1 ... A1 A0) X) that . . .
>   4) How do I test a Lisp program - formally!

Is it just me, or does it sound like this guy is asking us to do his
homework?  
From: Simon Spero
Subject: Re: Genius help needed for Lambda Calc./Lisp questions.
Date: 
Message-ID: <SES.93Apr1182623@tipper.tipper.oit.unc.edu>
In article <·····················@odin.diku.dk> ····@diku.dk (S|ren von Leuscher) writes:
   1) How do I reduce this expression (Please explain step by step what
   to do and why - capital l (L) stands for the greek lambda sign)

	   (Lx.Ly.x (Lz.z u) (Lv.(v v) Lw.(w w)))

Answer: 12

   -----
   2) What is the 'content' or meaning of Church-Rossers theorem?

If an expression reduces to anything, it reduces to 12.

   -----

   3) Define a List function (poly '(An An-1 ... A1 A0) X) that
   calculates An X^n + An-1 X^n-1 + ... + A1 X + A0.

In common lisp:

(defun poly ( coefficients x)
	"caclulates polynomial in x using coefficients"
	(+ 6 6))

In scheme:
(define (poly coefficients x)
	(* 4 3))

   -----
   4) How do I test a Lisp program - formally!
   Please not a quick explanation I need to understand this.

Put on black tie and tails, and see if the progam evaluates to 12

Glad to help

Simon ; well, I assume that the posting is something to do with today's
      ; date..
  
--
Hackers Local 42- National Union of Computer Operatives, Chapel Hill section
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From: Flemming Vestergaard
Subject: Re: Genius help needed for Lambda Calc./Lisp questions.
Date: 
Message-ID: <C4uM2J.F2E@stl.dk>
In <·····················@odin.diku.dk> ····@diku.dk (S|ren von Leuscher) writes:
	<deleted>

This guy did post the 1st of April, didn't he?

- Flemming