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Some of the enhancements from Perl1 included:
* New regexp routines derived from Henry Spencer's.
o Support for /(foo|bar)/.
o Support for /(foo)*/ and /(foo)+/.
o \s for whitespace, \S for non-, \d for digit, \D nondigit
* 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.
* Use of <> in array contexts returns the whole file or glob list.
* New iterator for normal arrays, foreach, that allows both read and write.
* 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>;
* 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.
* There is now a wait operator.
* There is now a sort operator.
* The manual is now not lying when it says that perl is generally faster than sed. I hope.
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[ Perl is kind of designed to make awk and sed semi-obsolete. This posting
will include the first 10 patches after the main source. The following
description is lifted from Larry's manpage. --r$ ]
Perl is a interpreted language optimized for scanning arbitrary text
files, extracting information from those text files, and printing
reports based on that information. It's also a good language for many
system management tasks. The language is intended to be practical
(easy to use, efficient, complete) rather than beautiful (tiny,
elegant, minimal). It combines (in the author's opinion, anyway) some
of the best features of C, sed, awk, and sh, so people familiar with
those languages should have little difficulty with it. (Language
historians will also note some vestiges of csh, Pascal, and even
BASIC-PLUS.) Expression syntax corresponds quite closely to C
expression syntax. If you have a problem that would ordinarily use sed
or awk or sh, but it exceeds their capabilities or must run a little
faster, and you don't want to write the silly thing in C, then perl may
be for you. There are also translators to turn your sed and awk
scripts into perl scripts.
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