perldiag: Wrap long lines

[perl5.git] / pod / perltie.pod

diff --git a/pod/perltie.pod b/pod/perltie.pod
index 0323e32..a200acc 100644 (file)
--- a/pod/perltie.pod
+++ b/pod/perltie.pod
@@ -134,8 +134,8 @@ X<STORE>
 
 This method will be triggered every time the tied variable is set
 (assigned).  Beyond its self reference, it also expects one (and only one)
-argument--the new value the user is trying to assign. Don't worry about
-returning a value from STORE -- the semantic of assignment returning the
+argument: the new value the user is trying to assign. Don't worry about
+returning a value from STORE; the semantic of assignment returning the
 assigned value is implemented with FETCH.
 
     sub STORE {
@@ -195,7 +195,8 @@ TIESCALAR classes are certainly possible.
 X<array, tying>
 
 A class implementing a tied ordinary array should define the following
-methods: TIEARRAY, FETCH, STORE, FETCHSIZE, STORESIZE and perhaps UNTIE and/or DESTROY.
+methods: TIEARRAY, FETCH, STORE, FETCHSIZE, STORESIZE, CLEAR
+and perhaps UNTIE and/or DESTROY.
 
 FETCHSIZE and STORESIZE are used to provide C<$#array> and
 equivalent C<scalar(@array)> access.
@@ -673,9 +674,9 @@ method on the original object reference returned by tie().
        croak "@{[&whowasi]}: $file not clobberable"
            unless $self->{CLOBBER};
 
-       open(F, "> $file") || croak "can't open $file: $!";
-       print F $value;
-       close(F);
+       open(my $f, '>', $file) || croak "can't open $file: $!";
+       print $f $value;
+       close($f);
     }
 
 If they wanted to clobber something, they might say:
@@ -869,6 +870,12 @@ All of this is especially useful when perl is embedded in some other
 program, where output to STDOUT and STDERR may have to be redirected 
 in some special way.  See nvi and the Apache module for examples.
 
+When tying a handle, the first argument to C<tie> should begin with an
+asterisk.  So, if you are tying STDOUT, use C<*STDOUT>.  If you have
+assigned it to a scalar variable, say C<$handle>, use C<*$handle>.
+C<tie $handle> ties the scalar variable C<$handle>, not the handle inside
+it.
+
 In our example we're going to create a shouting handle.
 
     package Shout;
@@ -940,10 +947,25 @@ or C<sysread> functions.
 =item READLINE this
 X<READLINE>
 
-This method will be called when the handle is read from via <HANDLE>.
-The method should return undef when there is no more data.
-
-    sub READLINE { $r = shift; "READLINE called $$r times\n"; }
+This method is called when the handle is read via C<E<lt>HANDLEE<gt>>
+or C<readline HANDLE>.
+
+As per L<C<readline>|perlfunc/readline>, in scalar context it should return
+the next line, or C<undef> for no more data.  In list context it should
+return all remaining lines, or an empty list for no more data.  The strings
+returned should include the input record separator C<$/> (see L<perlvar>),
+unless it is C<undef> (which means "slurp" mode).
+
+    sub READLINE {
+      my $r = shift;
+      if (wantarray) {
+        return ("all remaining\n",
+                "lines up\n",
+                "to eof\n");
+      } else {
+        return "READLINE called " . ++$$r . " times\n";
+      }
+    }
 
 =item GETC this
 X<GETC>
@@ -1078,7 +1100,7 @@ This is the output when it is executed:
 So far so good.  Those of you who have been paying attention will have
 spotted that the tied object hasn't been used so far.  So lets add an
 extra method to the Remember class to allow comments to be included in
-the file -- say, something like this:
+the file; say, something like this:
 
     sub comment {
         my $self = shift;