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authorPerl 5 Porters <perl5-porters@africa.nicoh.com>1997-03-26 07:04:34 +1200
committerChip Salzenberg <chip@atlantic.net>1997-03-26 07:04:34 +1200
commit54310121b442974721115f93666234a200f5c7e4 (patch)
tree99b5953030ddf062d77206ac0cf8ac967e7cbd93 /pod/perlfaq6.pod
parentd03407ef6d8e534a414e9ce92c6c5c8dab664a40 (diff)
downloadperl-54310121b442974721115f93666234a200f5c7e4.tar.gz
[inseperable changes from patch from perl-5.003_95 to perl-5.003_86]
[editor's note: this commit was prepared manually so may differ in minor ways to other inseperable changes commits] CORE LANGUAGE CHANGES Title: "Support $ENV{PERL5OPT}" From: Chip Salzenberg Files: perl.c pod/perldiag.pod pod/perldelta.pod pod/perlrun.pod Title: "Implement void context, in which C<wantarray> is undef" From: Chip Salzenberg Files: cop.h doop.c dump.c global.sym gv.c op.c op.h perl.c pod/perlcall.pod pod/perldelta.pod pod/perlfunc.pod pod/perlguts.pod pod/perlsub.pod pp.c pp_ctl.c pp_hot.c pp_sys.c proto.h Title: "Don't look up &AUTOLOAD in @ISA when calling plain function" From: Chip Salzenberg Files: global.sym gv.c lib/Text/ParseWords.pm pod/perldelta.pod pp_hot.c proto.h t/op/method.t Title: "Allow closures to be constant subroutines" From: Chip Salzenberg Files: op.c Title: "Make C<scalar(reverse)> mean C<scalar(reverse $_)>" From: Chip Salzenberg Files: pp.c Title: "Fix lexical suicide from C<my $x = $x> in sub" From: Chip Salzenberg Files: op.c Title: "Make "Unrecog. char." fatal, and update its doc" From: Chip Salzenberg Files: pod/perldiag.pod toke.c CORE PORTABILITY Title: "safefree() mismatch" From: Roderick Schertler Msg-ID: <21338.859653381@eeyore.ibcinc.com> Date: Sat, 29 Mar 1997 11:36:21 -0500 Files: util.c (applied based on p5p patch as commit id 9b9b466fb02dc96c81439bafbb3b2da55238cfd2) Title: "Win32 update (seven patches)" From: Gurusamy Sarathy and Nick Ing-Simmons Files: EXTERN.h MANIFEST win32/Makefile win32/perl.mak win32/perl.rc win32/perldll.mak win32/makedef.pl win32/modules.mak win32/win32io.c win32/bin/pl2bat.bat OTHER CORE CHANGES Title: "Report PERL* environment variables in -V and perlbug" From: Chip Salzenberg Files: perl.c utils/perlbug.PL Title: "Typo in perl.c: Printing NO_EMBED for perl -V" From: Gisle Aas Msg-ID: <199703301922.VAA13509@furubotn.sn.no> Date: Sun, 30 Mar 1997 21:22:11 +0200 Files: perl.c (applied based on p5p patch as commit id b6c639e4b1912ad03b9b10ba9518d96bd0a6cfaf) Title: "Don't let C<$var = $var> untaint $var" From: Chip Salzenberg Files: pp_hot.c pp_sys.c sv.h t/op/taint.t Title: "Fix autoviv bug in C<my $x; ++$x->{KEY}>" From: Chip Salzenberg Files: pp_hot.c Title: "Re: 5.004's new srand() default seed" From: Hallvard B Furuseth Msg-ID: <199703302219.AAA20998@bombur2.uio.no> Date: Mon, 31 Mar 1997 00:19:13 +0200 (MET DST) Files: pp.c (applied based on p5p patch as commit id d7d933a26349f945f93b2f0dbf85b773d8ca3219) Title: "Re: embedded perl and top_env problem " From: Gurusamy Sarathy Msg-ID: <199703280031.TAA05711@aatma.engin.umich.edu> Date: Thu, 27 Mar 1997 19:31:42 -0500 Files: gv.c interp.sym perl.c perl.h pp_ctl.c pp_sys.c scope.h util.c (applied based on p5p patch as commit id f289f7d2518e7a8a82114282e774adf50fa6ce85) Title: "Define and use new macro: boolSV()" From: Tim Bunce Files: gv.c lib/ExtUtils/typemap os2/os2.c pp.c pp_hot.c pp_sys.c sv.c sv.h universal.c vms/vms.c Title: "Re: strict @F" From: Hallvard B Furuseth Msg-ID: <199703252110.WAA16038@bombur2.uio.no> Date: Tue, 25 Mar 1997 22:10:33 +0100 (MET) Files: toke.c (applied based on p5p patch as commit id dfd44a5c8c8dd4c001c595debfe73d011a96d844) Title: "Try harder to identify errors at EOF" From: Chip Salzenberg Files: toke.c Title: "Minor string change in toke.c: 'bareword'" From: lvirden@cas.org Msg-ID: <1997Mar27.130247.1911552@hmivax.humgen.upenn.edu> Date: Thu, 27 Mar 1997 13:02:46 -0500 (EST) Files: toke.c (applied based on p5p patch as commit id 9b56c8f8085a9e773ad87c6b3c1d0b5e39dbc348) Title: "Improve diagnostic on \r in program text" From: Chip Salzenberg Files: pod/perldiag.pod toke.c Title: "Make Sock_size_t typedef work right" From: Chip Salzenberg Files: perl.h pp_sys.c LIBRARY AND EXTENSIONS Title: "New module constant.pm" From: Tom Phoenix Files: MANIFEST lib/constant.pm op.c pp.c t/pragma/constant.t Title: "Remove chat2" From: Chip Salzenberg Files: MANIFEST lib/chat2.inter lib/chat2.pl Title: "Include CGI.pm 2.32" From: Chip Salzenberg Files: MANIFEST eg/cgi/* lib/CGI.pm lib/CGI/Apache.pm lib/CGI/Carp.pm lib/CGI/Fast.pm lib/CGI/Push.pm lib/CGI/Switch.pm UTILITIES Title: "Tom C's Pod::Html and html tools, as of 30 March 97" From: Chip Salzenberg Files: MANIFEST installhtml lib/Pod/Html.pm pod/pod2html.PL Title: "Fix path bugs in installhtml" From: Robin Barker <rmb1@cise.npl.co.uk> Msg-ID: <3180.9703270906@tempest.cise.npl.co.uk> Date: Thu, 27 Mar 97 09:06:14 GMT Files: installhtml Title: "Make perlbug say that it's only for core Perl bugs" From: Chip Salzenberg Files: utils/perlbug.PL DOCUMENTATION Title: "Document autouse and constant; update diagnostics" From: Chip Salzenberg Files: pod/perldelta.pod Title: "Suggest to upgraders that they try '-w' again" From: Hallvard B Furuseth Msg-ID: <199703251901.UAA15982@bombur2.uio.no> Date: Tue, 25 Mar 1997 20:01:26 +0100 (MET) Files: pod/perldelta.pod (applied based on p5p patch as commit id 4176c059b9ba6b022e99c44270434a5c3e415b73) Title: "Improve and update documentation of constant subs" From: Tom Phoenix <rootbeer@teleport.com> Msg-ID: <Pine.GSO.3.96.970331122546.14185C-100000@kelly.teleport.com> Date: Mon, 31 Mar 1997 13:05:54 -0800 (PST) Files: pod/perlsub.pod Title: "Improve documentation of C<return>" From: Chip Salzenberg Files: pod/perlfunc.pod pod/perlsub.pod Title: "perlfunc.pod patch" From: Gisle Aas Msg-ID: <199703262159.WAA17531@furubotn.sn.no> Date: Wed, 26 Mar 1997 22:59:23 +0100 Files: pod/perlfunc.pod (applied based on p5p patch as commit id 35a731fcbcd7860eb497d6598f3f77b8746319c4) Title: "Use 'while (defined($x = <>)) {}', per <gnat@frii.com>" From: Chip Salzenberg Files: configpm lib/Term/Cap.pm perlsh pod/perlipc.pod pod/perlop.pod pod/perlsub.pod pod/perlsyn.pod pod/perltrap.pod pod/perlvar.pod win32/bin/search.bat Title: "Document and test C<%> behavior with negative operands" From: Chip Salzenberg Files: pod/perlop.pod t/op/arith.t Title: "Update docs on $]" From: Chip Salzenberg Files: pod/perlvar.pod Title: "perlvar.pod patch" From: Gisle Aas Msg-ID: <199703261254.NAA10237@bergen.sn.no> Date: Wed, 26 Mar 1997 13:54:00 +0100 Files: pod/perlvar.pod (applied based on p5p patch as commit id 0aa182cb0caa3829032904b9754807b1b7418509) Title: "Fix example of C<or> vs. C<||>" From: Chip Salzenberg Files: pod/perlsyn.pod Title: "Pod usage and spelling patch" From: Larry W. Virden Files: pod/*.pod Title: "Pod updates" From: "Cary D. Renzema" <caryr@mxim.com> Msg-ID: <199703262353.PAA01819@macs.mxim.com> Date: Wed, 26 Mar 1997 15:53:22 -0800 (PST) Files: pod/*.pod (applied based on p5p patch as commit id 5695b28edc67a3f45e8a0f25755d07afef3660ac)
Diffstat (limited to 'pod/perlfaq6.pod')
-rw-r--r--pod/perlfaq6.pod50
1 files changed, 25 insertions, 25 deletions
diff --git a/pod/perlfaq6.pod b/pod/perlfaq6.pod
index 0adebd72fe..1cec15c669 100644
--- a/pod/perlfaq6.pod
+++ b/pod/perlfaq6.pod
@@ -11,7 +11,7 @@ with regular expressions, but those answers are found elsewhere in
this document (in the section on Data and the Networking one on
networking, to be precise).
-=head2 How can I hope to use regular expressions without creating illegible and unmaintainable code?
+=head2 How can I hope to use regular expressions without creating illegible and unmaintainable code?
Three techniques can make regular expressions maintainable and
understandable.
@@ -96,8 +96,8 @@ record read in.
while ( <> ) {
while ( /\b(\w\S+)(\s+\1)+\b/gi ) {
print "Duplicate $1 at paragraph $.\n";
- }
- }
+ }
+ }
Here's code that finds sentences that begin with "From " (which would
be mangled by many mailers):
@@ -138,7 +138,7 @@ on matching balanced text.
$/ must be a string, not a regular expression. Awk has to be better
for something. :-)
-Actually, you could do this if you don't mind reading the whole file into
+Actually, you could do this if you don't mind reading the whole file into
undef $/;
@records = split /your_pattern/, <FH>;
@@ -217,10 +217,10 @@ See L<perllocale>.
=head2 How can I match a locale-smart version of C</[a-zA-Z]/>?
One alphabetic character would be C</[^\W\d_]/>, no matter what locale
-you're in. Non-alphabetics would be C</[\W\d_]/> (assuming you don't
+you're in. Non-alphabetics would be C</[\W\d_]/> (assuming you don't
consider an underscore a letter).
-=head2 How can I quote a variable to use in a regexp?
+=head2 How can I quote a variable to use in a regexp?
The Perl parser will expand $variable and @variable references in
regular expressions unless the delimiter is a single quote. Remember,
@@ -240,7 +240,7 @@ Without the \Q, the regexp would also spuriously match "di".
=head2 What is C</o> really for?
-Using a variable in a regular expression match forces a re-evaluation
+Using a variable in a regular expression match forces a reevaluation
(and perhaps recompilation) each time through. The C</o> modifier
locks in the regexp the first time it's used. This always happens in a
constant regular expression, and in fact, the pattern was compiled
@@ -325,13 +325,13 @@ playing hot potato.
Use the split function:
while (<>) {
- foreach $word ( split ) {
+ foreach $word ( split ) {
# do something with $word here
- }
- }
+ }
+ }
-Note that this isn't really a word in the English sense; it's just
-chunks of consecutive non-whitespace characters.
+Note that this isn't really a word in the English sense; it's just
+chunks of consecutive non-whitespace characters.
To work with only alphanumeric sequences, you might consider
@@ -344,25 +344,25 @@ To work with only alphanumeric sequences, you might consider
=head2 How can I print out a word-frequency or line-frequency summary?
To do this, you have to parse out each word in the input stream. We'll
-pretend that by word you mean chunk of alphabetics, hyphens, or
-apostrophes, rather than the non-whitespace chunk idea of a word given
+pretend that by word you mean chunk of alphabetics, hyphens, or
+apostrophes, rather than the non-whitespace chunk idea of a word given
in the previous question:
while (<>) {
while ( /(\b[^\W_\d][\w'-]+\b)/g ) { # misses "`sheep'"
$seen{$1}++;
- }
- }
+ }
+ }
while ( ($word, $count) = each %seen ) {
print "$count $word\n";
- }
+ }
If you wanted to do the same thing for lines, you wouldn't need a
regular expression:
- while (<>) {
+ while (<>) {
$seen{$_}++;
- }
+ }
while ( ($line, $count) = each %seen ) {
print "$count $line";
}
@@ -495,7 +495,7 @@ Of course, that could have been written as
while (<>) {
chomp;
PARSER: {
- if ( /\G( \d+\b )/gx {
+ if ( /\G( \d+\b )/gx {
print "number: $1\n";
redo PARSER;
}
@@ -520,7 +520,7 @@ But then you lose the vertical alignment of the regular expressions.
While it's true that Perl's regular expressions resemble the DFAs
(deterministic finite automata) of the egrep(1) program, they are in
-fact implemented as NFAs (non-deterministic finite automata) to allow
+fact implemented as NFAs (nondeterministic finite automata) to allow
backtracking and backreferencing. And they aren't POSIX-style either,
because those guarantee worst-case behavior for all cases. (It seems
that some people prefer guarantees of consistency, even when what's
@@ -538,7 +538,7 @@ side-effects, and side-effects can be mystifying. There's no void
grep() that's not better written as a C<for> (well, C<foreach>,
technically) loop.
-=head2 How can I match strings with multi-byte characters?
+=head2 How can I match strings with multibyte characters?
This is hard, and there's no good way. Perl does not directly support
wide characters. It pretends that a byte and a character are
@@ -578,7 +578,7 @@ Or like this:
Or like this:
while ($martian =~ m/\G([A-Z][A-Z]|.)/gs) { # \G probably unneeded
- print "found GX!\n", last if $1 eq 'GX';
+ print "found GX!\n", last if $1 eq 'GX';
}
Or like this:
@@ -586,11 +586,11 @@ Or like this:
die "sorry, Perl doesn't (yet) have Martian support )-:\n";
In addition, a sample program which converts half-width to full-width
-katakana (in Shift-JIS or EUC encoding) is available from CPAN as
+katakana (in Shift-JIS or EUC encoding) is available from CPAN as
=for Tom make it so
-There are many double- (and multi-) byte encodings commonly used these
+There are many double (and multi) byte encodings commonly used these
days. Some versions of these have 1-, 2-, 3-, and 4-byte characters,
all mixed.