From: "Paul Gilmartin" <[email protected]>
Sent: Tuesday, October 22, 2013 1:42 AM
On 2013-10-21, at 07:13, John Gilmore wrote:
Perhaps also worth noting explicitly is that the linear-search scheme
done well is not significantly less complex than the binary-search
one.
You've earlier advocated the value of comparison operands having
a ternary result. Of course this is available in (zSeries)
assembler. It might typically shorten a table search by one
iteration.
How is that?
o What HLLs provide ternary comparison operators?
o Is an optimizing compiler likely to collapse two consecutive
comparisions with identical operands into a single comparison
operation followed by two conditional branches?
o In what langages does a comparison yield a ternary R-value; one
which could be assigned to a variable for future use?
(Assembler could be considered to provide this by storing the
condition code in the program mask.)
PL/I provides the COMPARE built-in function, that compares
two operands and delivers -1, 0, or +1.
