lwall@devvax.JPL.NASA.GOV (Larry Wall) (06/05/88)
Version 2.0 of perl has been released. It has been mailed to comp.sources.unix
and is also available by anonymous ftp from my site, jpl-devvax.jpl.nasa.gov
(128.149.8.43), directory pub/perl.2.0. Enjoy!
Larry Wall
lwall@jpl-devvax.jpl.nasa.gov
P.S. Here's the latest list of changes from 1.0 (patchlevel 29) to 2.0. If you
have played with a beta version, the latest changes are at the end.
New regexp routines derived from Henry Spencer's.
Support for /(foo|bar)/.
Support for /(foo)*/ and /(foo)+/.
\s for whitespace, \S nonwhitespace
\d for digit, \D nondigit
much faster
Local variables in blocks, subroutines and evals.
Recursive subroutine calls are now supported.
Array values may now be interpolated into lists:
unlink 'foo', 'bar', @trashcan, 'tmp';
File globbing via <*.foo>.
Use of <> in array contexts returns the whole file or glob list:
unlink <*.foo>;
New iterator for normal arrays, foreach, that allows both read and write:
foreach $elem (@array) {
$elem =~ s/foo/bar/;
}
Ability to open pipe to a forked off script for secure pipes in setuid scripts.
File inclusion via
do 'foo.pl';
More file tests, including -t to see if, for instance, stdin is
a terminal. File tests now behave in a more correct manner. You can do
file tests on filehandles as well as filenames. The special filetests
-T and -B test a file to see if it's text or binary.
An eof can now be used on each file of the <> input for such purposes
as resetting the line numbers or appending to each file of an inplace edit.
Assignments can now function as lvalues, so you can say things like
($HOST = $host) =~ tr/a-z/A-Z/;
($obj = $src) =~ s/\.c$/.o/;
You can now do certain file operations with a variable which holds the name
of a filehandle, e.g. open(++$incl,$includefilename); $foo = <$incl>;
You can now a subroutine indirectly through a scalar variable:
$which = 'xyz';
do $which('foo'); # calls xyz
Warnings are now available (with -w) on use of uninitialized variables and on
identifiers that are mentioned only once, and on reference to various
undefined things.
The -S switch causes perl to search the PATH for the script so that you can say
eval "exec /usr/bin/perl -S $0 $*"
if $running_under_some_shell;
Reset now resets arrays and associative arrays as well as string variables.
Assigning off the end of an array now nulls out any intervening values.
$#foo is now an lvalue. You can preallocate or truncate arrays, or recover
values lost to prior truncation.
$#foo is now indexed to $[ properly.
s/foo/bar/i optimization bug fixed.
The $x = "...$x..."; bug is fixed.
The @ary = (1); bug is now fixed. You can even say @ary = 1;
$= now returns the correct value.
Several of the larger files are now split into smaller pieces for easier
compilation.
Pattern matches evaluated in an array context now return ($1, $2...).
There is now a wait operator.
There is now a sort operator.
The requirement of parens around certain expressions when taking their value
has been lifted. In particular, you can say
$x = print "foo","bar";
$x = unlink "foo","bar";
chdir "foo" || die "Can't chdir to foo\n";
The manual is now not lying when it says that perl is generally faster than
sed. I hope.