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Diffstat (limited to 'Changes')
| -rw-r--r-- | Changes | 65 |
1 files changed, 61 insertions, 4 deletions
@@ -1,18 +1,75 @@ - +Incompatibilities +----------------- s'$lhs'$rhs' now does no interpolation on either side. It used to interplolate $lhs but not $rhs. The second and third arguments of splice are now evaluated in scalar context (like the book says) rather than list context. - Saying shift @foo + 20 is now a semantic error. + Saying "shift @foo + 20" is now a semantic error because of precedence. + + "open FOO || die" is now incorrect. You need parens around the filehandle. The elements of argument lists for formats are now evaluated in list - context. + context. This means you can interpolate list values now. - You can't do a goto into a block that is optimized away. + You can't do a goto into a block that is optimized away. Darn. It is no longer syntactically legal to use whitespace as the name of a variable. Some error messages will be different. + + The caller function now a false value in a scalar context if there is + no caller. This lets library files determine if they're being required. + + m//g now attaches its state to the searched string rather than the + regular expression. + +New things +---------- + The -w switch is much more informative. + + References. See t/op/ref.t for examples. + + Objects. See t/op/ref.t for examples. + + => is now a synonym for comma. This is useful as documentation for + arguments that come in pairs, such as initializers for associative arrays, + or named arguments to a subroutine. + + All functions have been turned into list operators or unary operators, + meaning the parens are optional. Even subroutines may be called as + list operators if they've already been declared. + + More embeddible. See main.c and embed_h.SH. + + The interpreter is now flattened out. Compare Perl 4's eval.c with + the perl 5's pp.c. Compare Perl 4's 900 line interpreter loop in cmd.c + with Perl 5's 1 line interpreter loop in run.c. Eventually we'll make + everything non-blocking so we can interface nicely with a scheduler. + + eval is now treated more like a subroutine call. Among other things, + this means you can return from it. + + Format value lists may be spread over multiple lines by enclosing in + curlies. + + You may now define BEGIN and END subroutines for each package. The BEGIN + subroutine executes the moment it's parsed. The END subroutine executes + just before exiting. + + Flags on the #! line are interpreted even if the script wasn't + executed directly. (And even if the script was located by "perl -x"!) + + The ?: operator is now legal as an lvalue. + + List context now propagates to the right side of && and ||, as well + as the 2nd and 3rd arguments to ?:. + + The "defined" function can now take a general expression. + + Lexical scoping available via "my". eval can see the current lexical + variables. + + Saying "package;" requires explicit package name on global symbols. |