where did the EXPR1 if EXPR2 documentation go?

I believe the Camel book says that

  EXPR1 if EXPR2;

is synonymous with:

  EXPR2 && EXPR1;

And that

  EXPR1 unless EXPR2;

is synonymous with:

  EXPR2 || EXPR1;

Well, I can't find this in perlsyn (or anywhere else).  And I've not yet
checked the Camel, but this is a SLIGHT untruth.

I can say:

  $foo = (this() || that());

but I can't say:

  $foo = (that() unless this());

The reason I'm asking about this is because I was recently given a poser
as to why:

  @array = (1,0,0,1,0);
  print scalar grep { 1 if !$_ } @array;
  print scalar grep { 1 unless $_ } @array;

printed TWO different numbers.  "Isn't unless $_ the same as if
!$_?"  Well, I had to convince them that the ``A if B'' is really ``B ||
A'', and it's not in the Perl docs, and I told them they had to believe
me. :)

-- 
MIDN 4/C PINYAN, NROTCURPI, US Naval Reserve             japhy@pobox.com
http://www.pobox.com/~japhy/                  http://pinyaj.stu.rpi.edu/
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• where did the EXPR1 if EXPR2 documentation go? by Jeff Pinyan
• Re: where did the EXPR1 if EXPR2 documentation go? by Nathan Torkington