Author: larry Date: Mon Dec 3 15:55:10 2007 New Revision: 14470 Modified: doc/trunk/design/syn/S02.pod doc/trunk/design/syn/S05.pod
Log: Mention that Int assumes 2's complement semantics when viewed via bitops. Modified: doc/trunk/design/syn/S02.pod ============================================================================== --- doc/trunk/design/syn/S02.pod (original) +++ doc/trunk/design/syn/S02.pod Mon Dec 3 15:55:10 2007 @@ -12,9 +12,9 @@ Maintainer: Larry Wall <[EMAIL PROTECTED]> Date: 10 Aug 2004 - Last Modified: 26 Sep 2007 + Last Modified: 3 Dec 2007 Number: 2 - Version: 119 + Version: 120 This document summarizes Apocalypse 2, which covers small-scale lexical items and typological issues. (These Synopses also contain @@ -616,6 +616,10 @@ Perl 6 intrinsically supports big integers and rationals through its system of type declarations. C<Int> automatically supports promotion to arbitrary precision, as well as holding C<Inf> and C<NaN> values. +Note that C<Int> assumes 2's complement arithmetic, so C<+^1 == -2> +is guaranteed. (Native C<int> operations need not support this on +machines that are not natively 2's complement. You must convert to +and from C<Int> to do portable bitops on such ancient hardware.) (C<Num> may support arbitrary-precision floating-point arithmetic, but is not required to unless we can do so portably and efficiently. C<Num> Modified: doc/trunk/design/syn/S05.pod ============================================================================== --- doc/trunk/design/syn/S05.pod (original) +++ doc/trunk/design/syn/S05.pod Mon Dec 3 15:55:10 2007 @@ -587,7 +587,7 @@ would allow any identifier (including any identifier containing "moose" as a substring) as long as the identifier as a whole is not -equal to "moose". (Note the anchors, which attach submatch to the +equal to "moose". (Note the anchors, which attach the submatch to the beginning and end of the identifier as if that were the entire match.) When used as part of a longer match, for clarity it might be good to use extra brackets:
