addendum to change#2823

	Message-ID: <13940.21805.470054.299@fre-76-120.reshall.berkeley.edu>
	Subject: [PATCH] Docs and tests for method-call syntax

p4raw-link: @2823 on //depot/perl: b1524f1739a84392b9443982741b38ce39195b6c

p4raw-id: //depot/perl@2844

diff --git a/pod/perlobj.pod b/pod/perlobj.pod
index 182e3ee..a997ae0 100644 (file)
--- a/pod/perlobj.pod
+++ b/pod/perlobj.pod
@@ -251,7 +251,7 @@ or in one statement,
 There are times when one syntax is more readable, and times when the
 other syntax is more readable.  The indirect object syntax is less
 cluttered, but it has the same ambiguity as ordinary list operators.
-Indirect object method calls are parsed using the same rule as list
+Indirect object method calls are usually parsed using the same rule as list
 operators: "If it looks like a function, it is a function".  (Presuming
 for the moment that you think two words in a row can look like a
 function name.  C++ programmers seem to think so with some regularity,
@@ -268,7 +268,20 @@ would be equivalent to
 
     Critter->new('Bam' x 2), 1.4, 45
 
-which is unlikely to do what you want.
+which is unlikely to do what you want.  Confusingly, however, this
+rule applies only when the indirect object is a bareword package name,
+not when it's a scalar, a BLOCK, or a C<Package::> qualified package name.
+In those cases, the arguments are parsed in the same way as an
+indirect object list operator like print, so
+
+    new Critter:: ('Bam' x 2), 1.4, 45
+
+is the same as
+
+   Critter::->new(('Bam' x 2), 1.4, 45)
+
+For more reasons why the indirect object syntax is ambiguous, see
+L<"WARNING"> below.
 
 There are times when you wish to specify which class's method to use.
 In this case, you can call your method as an ordinary subroutine

diff --git a/t/op/method.t b/t/op/method.t
index f1b1888..0912f1e 100755 (executable)
--- a/t/op/method.t
+++ b/t/op/method.t
@@ -4,7 +4,7 @@
 # test method calls and autoloading.
 #
 
-print "1..26\n";
+print "1..46\n";
 
 @A::ISA = 'B';
 @B::ISA = 'C';
@@ -19,6 +19,35 @@ sub test {
   print "ok ", ++$cnt, "\n"
 }
 
+# First, some basic checks of method-calling syntax:
+$obj = bless [], "Pack";
+sub Pack::method { shift; join(",", "method", @_) }
+$mname = "method";
+
+test(Pack->method("a","b","c"), "method,a,b,c");
+test(Pack->$mname("a","b","c"), "method,a,b,c");
+test(method Pack ("a","b","c"), "method,a,b,c");
+test((method Pack "a","b","c"), "method,a,b,c");
+
+test(Pack->method(), "method");
+test(Pack->$mname(), "method");
+test(method Pack (), "method");
+test(Pack->method, "method");
+test(Pack->$mname, "method");
+test(method Pack, "method");
+
+test($obj->method("a","b","c"), "method,a,b,c");
+test($obj->$mname("a","b","c"), "method,a,b,c");
+test((method $obj ("a","b","c")), "method,a,b,c");
+test((method $obj "a","b","c"), "method,a,b,c");
+
+test($obj->method(), "method");
+test($obj->$mname(), "method");
+test((method $obj ()), "method");
+test($obj->method, "method");
+test($obj->$mname, "method");
+test(method $obj, "method");
+
 test( A->d, "C::d");           # Update hash table;
 
 *B::d = \&D::d;                        # Import now.