----- Original Message -----
From: "Paul Gilmartin" <[email protected]>
To: <[email protected]>
Sent: Thursday, October 24, 2013 10:43 AM
Subject: Re: signum
On 2013-10-23 17:26, robin wrote:
In Rexx, this could be written with no (explicit) branches
as:
m = ( j > k ) - ( j < k );
In PL/I,
m = sign(j-k);
The objective was to synthesize sign() in a language such as
Rexx which, unlike PL/I, lacks it.
The KISS principle is worthy of more attention.
An IF construct is more obvious.
I have occasionally gotten
flamboyant and coded such as:
X = copies( 'gubbins', A==B ) /* instead of: */
You have to be joking.
if A==B
then X = 'gubbins'
else X = ''
Clearly, I've been polluted by excessive exposure to CDC 6600,
whose programmers went to extremes to avoid branches which
might break pipelining.
You can't avoid branches, either implicit or explicit.
On 2013-10-23 15:09, John Gilmore wrote:
Boolean values are bits in PL/I.
...
but nothing quite like your REXX construct is available.
IOW, PL/I provides no coercion from boolean (bit) values to
integer?
Conversion from boolean to integer is readily available in PL/I.
