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From: cslaurie@cybaswan.UUCP (Laurie Moseley )
Newsgroups: comp.lang.pascal
Subject: Function of semi-colon in Pascal (was: Pascal puzzle)
Keywords: Semi-colon
Message-ID: <2580@cybaswan.UUCP>
Date: 27 Jun 91 19:53:48 GMT
Lines: 52

This was posted recently:.................

<  confirm : boolean;
<  key     : char;
<
<begin
<  confirm := false;
<  key     := '0';
<  case key of
<    '1' : Menue1;
<    '2' : Menue2;
<    '3' : Menue3;
<    '0' : if confirm then
<            RequestExit;
<          else
<            FastExit;
<  end;
<end;
<
<This piece of program would compile OK, but I could never manage to
<get a FastExit! 
<Peter Knoerrich,        email: prknoerr@faui43.informatik.uni-erlangen.de
------------------------------------------------------------------------

I expected that this piece of code would not compile. The semi-colon
before the "else" means that a statement separator is coming in the
middle of a statement. In other words, there is a new statement beginning
with the word "else". It is as though you BEGAN a sentence with

 	Otherwise, go to the cinema ...

Anyway, I tried it out of curiosity, and sure enough it did not compile
(and it shouldn't). 

Once you delete that semi-colon, it will compile, but its behaviour is
precisely the opposite of that reported. As the boolean variable <confirm>
is set to <false> and is never changed, the condition for RequestExit is
never satisfied, so it will always FastExit.

==========================================================================

Laurie Moseley

Computer Science, University College, Swansea SA2 8PP, UK

Tel: +44 792 295399

JANET:	cslaurie@uk.ac.swan.pyr

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"Why does the Turing test set such abysmally low standards ?"
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