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From: "Craig A. Berry" <craigberry@nospam.mac.com>
Newsgroups: comp.os.vms
Subject: Re: basic BASIC question
Date: Fri, 31 Jan 2025 17:42:04 -0600
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On 1/31/25 4:05 PM, Dan Cross wrote:

> Treating -1 as true in BASIC seems rather common, from the quick
> survey I did; I speculate that this is almost certainly due to
> the bit representation of -1 having all bits set, while in BASIC
> the integer type is (usually?) signed, thus -1 on a two's
> complement machine.  I wonder what the original DTSS BASIC did?

I had a quick look at:

https://ia601901.us.archive.org/34/items/bitsavers_dartmouthB_3679804/BASIC_4th_Edition_Jan68_text.pdf

and didn't see an obvious answer, though I didn't read the whole thing
and could've missed something.  The exact values of true and false might
well have been considered an implementation detail that should not be
relied on.