X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/b4ebbc942f328f1a36f70b899d9165fa73484cd8..9deebca376903e87a5f8496ce3baf418d3e9d0b7:/lib/open.pm

diff --git a/lib/open.pm b/lib/open.pm
index 4515899..1bfe0d6 100644
--- a/lib/open.pm
+++ b/lib/open.pm
@@ -1,9 +1,7 @@
 package open;
 use warnings;
-use Carp;
-$open::hint_bits = 0x20000; # HINT_LOCALIZE_HH
 
-our $VERSION = '1.04';
+our $VERSION = '1.08';
 
 require 5.008001; # for PerlIO::get_layers()
 
@@ -14,6 +12,10 @@ sub _get_encname {
     return;
 }
 
+sub croak {
+    require Carp; goto &Carp::croak;
+}
+
 sub _drop_oldenc {
     # If by the time we arrive here there already is at the top of the
     # perlio layer stack an encoding identical to what we would like
@@ -39,13 +41,11 @@ sub _drop_oldenc {
     require Encode;
     my ($loname, $lcname) = _get_encname($old[-2]);
     unless (defined $lcname) { # Should we trust get_layers()?
-	require Carp;
-	Carp::croak("open: Unknown encoding '$loname'");
+	croak("open: Unknown encoding '$loname'");
     }
     my ($voname, $vcname) = _get_encname($new[-1]);
     unless (defined $vcname) {
-	require Carp;
-	Carp::croak("open: Unknown encoding '$voname'");
+	croak("open: Unknown encoding '$voname'");
     }
     if ($lcname eq $vcname) {
 	binmode($h, ":pop"); # utf8 is part of the encoding layer
@@ -56,7 +56,6 @@ sub import {
     my ($class,@args) = @_;
     croak("open: needs explicit list of PerlIO layers") unless @args;
     my $std;
-    $^H |= $open::hint_bits;
     my ($in,$out) = split(/\0/,(${^OPEN} || "\0"), -1);
     while (@args) {
 	my $type = shift(@args);
@@ -80,11 +79,7 @@ sub import {
 		    unless defined $locale_encoding;
 		(warnings::warnif("layer", "Cannot figure out an encoding to use"), last)
 		    unless defined $locale_encoding;
-		if ($locale_encoding =~ /^utf-?8$/i) {
-		    $layer = "utf8";
-		} else {
-		    $layer = "encoding($locale_encoding)";
-		}
+                $layer = "encoding($locale_encoding)";
 		$std = 1;
 	    } else {
 		my $target = $layer;		# the layer name itself
@@ -113,7 +108,7 @@ sub import {
 	    $in = $out = join(' ', @val);
 	}
 	else {
-	    croak "Unknown PerlIO layer class '$type'";
+	    croak "Unknown PerlIO layer class '$type' (need IN, OUT or IO)";
 	}
     }
     ${^OPEN} = join("\0", $in, $out);
@@ -152,7 +147,7 @@ open - perl pragma to set default PerlIO layers for input and output
 
     use open IO  => ':locale';
 
-    use open ':utf8';
+    use open ':encoding(utf8)';
     use open ':locale';
     use open ':encoding(iso-8859-7)';
 
@@ -168,9 +163,8 @@ The C<open> pragma serves as one of the interfaces to declare default
 "layers" (also known as "disciplines") for all I/O. Any two-argument
 open(), readpipe() (aka qx//) and similar operators found within the
 lexical scope of this pragma will use the declared defaults.
-Three-argument opens are not affected by this pragma since there you
-(can) explicitly specify the layers and are supposed to know what you
-are doing.
+Even three-argument opens may be affected by this pragma
+when they don't specify IO layers in MODE.
 
 With the C<IN> subpragma you can declare the default layers
 of input streams, and with the C<OUT> subpragma you can declare
@@ -179,7 +173,7 @@ you can control both input and output streams simultaneously.
 
 If you have a legacy encoding, you can use the C<:encoding(...)> tag.
 
-if you want to set your encoding layers based on your
+If you want to set your encoding layers based on your
 locale environment variables, you can use the C<:locale> tag.
 For example:
 
@@ -195,8 +189,8 @@ For example:
 
 These are equivalent
 
-    use open ':utf8';
-    use open IO => ':utf8';
+    use open ':encoding(utf8)';
+    use open IO => ':encoding(utf8)';
 
 as are these
 
@@ -212,23 +206,20 @@ The matching of encoding names is loose: case does not matter, and
 many encodings have several aliases.  See L<Encode::Supported> for
 details and the list of supported locales.
 
-Note that C<:utf8> PerlIO layer must always be specified exactly like
-that, it is not subject to the loose matching of encoding names.
-
-When open() is given an explicit list of layers they are appended to
-the list declared using this pragma.
+When open() is given an explicit list of layers (with the three-arg
+syntax), they override the list declared using this pragma.
 
 The C<:std> subpragma on its own has no effect, but if combined with
 the C<:utf8> or C<:encoding> subpragmas, it converts the standard
 filehandles (STDIN, STDOUT, STDERR) to comply with encoding selected
 for input/output handles.  For example, if both input and out are
-chosen to be C<:utf8>, a C<:std> will mean that STDIN, STDOUT, and
-STDERR are also in C<:utf8>.  On the other hand, if only output is
-chosen to be in C<< :encoding(koi8r) >>, a C<:std> will cause only the
-STDOUT and STDERR to be in C<koi8r>.  The C<:locale> subpragma
+chosen to be C<:encoding(utf8)>, a C<:std> will mean that STDIN, STDOUT,
+and STDERR are also in C<:encoding(utf8)>.  On the other hand, if only
+output is chosen to be in C<< :encoding(koi8r) >>, a C<:std> will cause
+only the STDOUT and STDERR to be in C<koi8r>.  The C<:locale> subpragma
 implicitly turns on C<:std>.
 
-The logic of C<:locale> is described in full in L</encoding>,
+The logic of C<:locale> is described in full in L<encoding>,
 but in short it is first trying nl_langinfo(CODESET) and then
 guessing from the LC_ALL and LANG locale environment variables.