Deprecate smartmatch

dist/Safe/t/safeops.t

@@ -453,7 +453,7 @@ dor		$x // $y
 dorassign	$x //= $y
 once		SKIP {use feature 'state'; state $foo = 42;}
 say		SKIP {use feature 'say'; say "foo";}
-smartmatch	no warnings 'experimental::smartmatch'; $x ~~ $y
+smartmatch	no warnings 'deprecated'; $x ~~ $y
 aeach		SKIP each @t
 akeys		SKIP keys @t
 avalues		SKIP values @t

lib/B/Deparse.t

@@ -1061,7 +1061,7 @@ my $c = [];
 my $d = \[];
 ####
 # SKIP ?$] < 5.010 && "smartmatch and given/when not implemented on this Perl version"
-# CONTEXT use feature ':5.10'; no warnings 'experimental::smartmatch';
+# CONTEXT use feature ':5.10'; no warnings 'deprecated';
 # implicit smartmatch in given/when
 given ('foo') {
     when ('bar') { continue; }
@@ -1624,7 +1624,7 @@ my @a;
 $a[0] = 1;
 ####
 # feature features without feature
-# CONTEXT no warnings 'experimental::smartmatch';
+# CONTEXT no warnings 'deprecated';
 CORE::state $x;
 CORE::say $x;
 CORE::given ($x) {
@@ -1640,7 +1640,7 @@ CORE::evalbytes '';
 () = CORE::fc $x;
 ####
 # feature features when feature has been disabled by use VERSION
-# CONTEXT no warnings 'experimental::smartmatch';
+# CONTEXT no warnings 'deprecated';
 use feature (sprintf(":%vd", $^V));
 use 1;
 CORE::say $_;
@@ -1670,7 +1670,7 @@ CORE::evalbytes '';
 () = CORE::__SUB__;
 ####
 # (the above test with CONTEXT, and the output is equivalent but different)
-# CONTEXT use feature ':5.10'; no warnings 'experimental::smartmatch';
+# CONTEXT use feature ':5.10'; no warnings 'deprecated';
 # feature features when feature has been disabled by use VERSION
 use feature (sprintf(":%vd", $^V));
 use 1;
@@ -1704,7 +1704,7 @@ CORE::evalbytes '';
 ####
 # SKIP ?$] < 5.017004 && "lexical subs not implemented on this Perl version"
 # lexical subroutines and keywords of the same name
-# CONTEXT use feature 'lexical_subs', 'switch'; no warnings 'experimental';
+# CONTEXT use feature 'lexical_subs', 'switch'; no warnings 'experimental'; no warnings 'deprecated';
 my sub default;
 my sub else;
 my sub elsif;

lib/overload.t

@@ -1910,7 +1910,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 
 
 	for my $sub (keys %subs) {
-	    no warnings 'experimental::smartmatch';
+	    no warnings 'deprecated';
 	    my $term = $subs{$sub};
 	    my $t = sprintf $term, '$_[0][0]';
 	    my $e ="sub { \$funcs .= '($sub)'; my \$r; if (\$use_int) {"
@@ -1952,7 +1952,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 				    ? "-\$_[0][0]"
 				    : "$_[3](\$_[0][0])";
 			my $r;
-			no warnings 'experimental::smartmatch';
+			no warnings 'deprecated';
 			if ($use_int) {
 			    use integer; $r = eval $e;
 			}
@@ -1999,7 +1999,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 	    $use_int = ($int ne '');
 	    my $plain = $tainted_val;
 	    my $plain_term = $int . sprintf $sub_term, '$plain';
-	    my $exp = do {no warnings 'experimental::smartmatch'; eval $plain_term };
+	    my $exp = do {no warnings 'deprecated'; eval $plain_term };
 	    diag("eval of plain_term <$plain_term> gave <$@>") if $@;
 	    SKIP: {
 		is_if_taint_supported(tainted($exp), $exp_taint,
@@ -2029,7 +2029,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 
 		    my $res_term  = $int . sprintf $sub_term, $var;
 		    my $desc =  "<$res_term> $ov_pkg" ;
-		    my $res = do { no warnings 'experimental::smartmatch'; eval $res_term };
+		    my $res = do { no warnings 'deprecated'; eval $res_term };
 		    diag("eval of res_term $desc gave <$@>") if $@;
 		    # uniquely, the inc/dec ops return the original
 		    # ref rather than a copy, so stringify it to

pod/perldiag.pod

@@ -2643,11 +2643,10 @@ C<getpwnam> operator returned an invalid UIC.
 forget to check the return value of your socket() call?  See
 L<perlfunc/getsockopt>.
 
-=item given is experimental
+=item given is deprecated
 
-(S experimental::smartmatch) C<given> depends on smartmatch, which
-is experimental, so its behavior may change or even be removed
-in any future release of perl.  See the explanation under
+(D deprecated) C<given> depends on smartmatch, which is deprecated. It
+will be removed in Perl 5.42.  See the explanation under
 L<perlsyn/Experimental Details on given and when>.
 
 =item Global symbol "%s" requires explicit package name (did you forget to
@@ -6038,14 +6037,13 @@ so there can't be any left to fill later parameters.
 overload it: Perl refuses to use the object's underlying structure
 for the smart match.
 
-=item Smartmatch is experimental
+=item Smartmatch is deprecated
 
-(S experimental::smartmatch) This warning is emitted if you
-use the smartmatch (C<~~>) operator.  This is currently an experimental
-feature, and its details are subject to change in future releases of
-Perl.  Particularly, its current behavior is noticed for being
-unnecessarily complex and unintuitive, and is very likely to be
-overhauled.
+(D deprecated) This warning is emitted if you
+use the smartmatch (C<~~>) operator.  This is a deprecated
+feature.  Particularly, its behavior is noticed for being
+unnecessarily complex and unintuitive, and it will be removed
+in Perl 5.42.
 
 =item Sorry, hash keys must be smaller than 2**31 bytes
 
@@ -8025,12 +8023,12 @@ but in actual fact, you got
 
 So put in parentheses to say what you really mean.
 
-=item when is experimental
+=item when is deprecated
 
-(S experimental::smartmatch) C<when> depends on smartmatch, which is
-experimental.  Additionally, it has several special cases that may
-not be immediately obvious, and their behavior may change or
-even be removed in any future release of perl.  See the explanation
+(D deprecated) C<when> depends on smartmatch, which is
+deprecated.  Additionally, it has several special cases that may
+not be immediately obvious, and it will be removed in Perl 5.42.
+See the explanation
 under L<perlsyn/Experimental Details on given and when>.
 
 =item Wide character in %s

pod/perlexperiment.pod

@@ -24,8 +24,12 @@ Introduced in Perl 5.10.0
 
 Modified in Perl 5.10.1, 5.12.0
 
+Deprecated in 5.38.0
+
+Will be removed in 5.42.0
+
 Using this feature triggers warnings in the category
-C<experimental::smartmatch>.
+C<deprecated>.
 
 The ticket for this experiment is
 L<[perl #13173]|https://github.com/Perl/perl5/issues/13173>.

regen/feature.pl

@@ -605,6 +605,9 @@ =head2 The 'switch' feature
 See L<perlsyn/"Switch Statements"> for details.
 
 This feature is available starting with Perl 5.10.
+It is deprecated starting with Perl 5.38, and using
+C<given>, C<when> or smartmatch will throw a warning.
+It will be removed in Perl 5.42.
 
 =head2 The 'unicode_strings' feature
 

regen/warnings.pl

@@ -171,7 +171,7 @@ BEGIN
 
 my %NAME_TO_VALUE; # ('NAME'       => index_number,       ....);
 
-# the experiments were successful,
+# the experiments were successful (or abandonned),
 # so no warning bit is needed anymore
 my %NO_BIT_FOR = map { ( uc $_ => 1, $_ => 1 ) } qw(
   experimental::lexical_subs
@@ -181,6 +181,7 @@ BEGIN
   experimental::alpha_assertions
   experimental::script_run
   experimental::isa
+  experimental::smartmatch
 );
 
 ###########################################################################

t/lib/croak/pp_ctl

@@ -11,14 +11,12 @@ no warnings 'deprecated';
 goto f;
 CORE::given(1){f:}
 EXPECT
-given is experimental at - line 3.
 Can't "goto" into a "given" block at - line 3.
 ########
 # NAME goto from given topic expression
 no warnings 'deprecated';
 CORE::given(goto f){f:}
 EXPECT
-given is experimental at - line 2.
 Can't "goto" into a "given" block at - line 2.
 ########
 # NAME goto into expression
@@ -41,7 +39,7 @@ EXPECT
 Can't find label foo at - line 3.
 ########
 # NAME when outside given
-use 5.01; no warnings 'experimental::smartmatch';
+use 5.01; no warnings 'deprecated';
 when(undef){}
 EXPECT
 Can't "when" outside a topicalizer at - line 2.

t/lib/feature/switch

@@ -3,28 +3,28 @@ Check the lexical scoping of the switch keywords.
 
 __END__
 # No switch; given should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT given;
 EXPECT
 Unquoted string "given" may clash with future reserved word at - line 3.
 given
 ########
 # No switch; when should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT when;
 EXPECT
 Unquoted string "when" may clash with future reserved word at - line 3.
 when
 ########
 # No switch; default should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT default;
 EXPECT
 Unquoted string "default" may clash with future reserved word at - line 3.
 default
 ########
 # No switch; break should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT break;
 EXPECT
 Unquoted string "break" may clash with future reserved word at - line 3.
@@ -36,19 +36,19 @@ EXPECT
 Can't "continue" outside a when block at - line 2.
 ########
 # Use switch; so given is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given("okay\n") { print }
 EXPECT
 okay
 ########
 # Use switch; so when is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given(1) { when(1) { print "okay" } }
 EXPECT
 okay
 ########
 # Use switch; so default is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given(1) { default { print "okay" } }
 EXPECT
 okay
@@ -60,7 +60,7 @@ EXPECT
 Can't "break" outside a given block at - line 3.
 ########
 # switch out of scope; given should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) {print "Okay here\n";}
 }
@@ -71,7 +71,7 @@ Okay here
 given
 ########
 # switch out of scope; when should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { when(1) {print "Okay here\n";} }
 }
@@ -82,7 +82,7 @@ Okay here
 when
 ########
 # switch out of scope; default should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { default {print "Okay here\n";} }
 }
@@ -93,7 +93,7 @@ Okay here
 default
 ########
 # switch out of scope; break should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { break }  
 }
@@ -103,7 +103,7 @@ Unquoted string "break" may clash with future reserved word at - line 6.
 break
 ########
 # C<no feature 'switch'> should work
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 given (1) { when(1) {print "Okay here\n";} }
 no feature 'switch';
@@ -114,7 +114,7 @@ Okay here
 when
 ########
 # C<no feature> should work too
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 given (1) { when(1) {print "Okay here\n";} }
 no feature;
@@ -125,14 +125,14 @@ Okay here
 when
 ########
 # Without the feature, no 'Unambiguous use of' warning:
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 @break = ($break = "break");
 print ${break}, ${break[0]};
 EXPECT
 breakbreak
 ########
 # With the feature, we get an 'Unambiguous use of' warning:
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 @break = ($break = "break");
 print ${break}, ${break[0]};

t/lib/warnings/9uninit

@@ -1943,7 +1943,7 @@ $v = 1 + prototype $fn;
 EXPECT
 Use of uninitialized value in addition (+) at - line 4.
 ########
-use warnings 'uninitialized'; no warnings 'experimental::smartmatch';
+use warnings 'uninitialized'; no warnings 'deprecated';
 my $v;
 my $fn = sub {};
 $v = 1 + (1 ~~ $fn);

t/lib/warnings/op

@@ -363,7 +363,7 @@ OPTION fatal
 Can't use an array as a reference at - line 3.
 ########
 # op.c
-use warnings 'void' ; no warnings 'experimental::smartmatch'; close STDIN ;
+use warnings 'void' ; no warnings 'deprecated'; close STDIN ;
 #line 2
 1 x 3 ;			# OP_REPEAT (folded)
 (1) x 3 ;		# OP_REPEAT

t/op/cmpchain.t

@@ -7,26 +7,28 @@ BEGIN {
 }
 
 use feature "isa";
-no warnings qw(experimental::smartmatch);
 
 my @cheqop = qw(== != eq ne);
 my @nceqop = qw(<=> cmp ~~);
 my @chrelop = qw(< > <= >= lt gt le ge);
 my @ncrelop = qw(isa);
 
 foreach my $c0 (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $c1 (@nceqop) {
 	is eval("sub { \$a $c0 \$b $c1 \$c }"), undef,
 	    "$c0 $c1 non-associative";
     }
 }
 foreach my $c (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $e (@cheqop) {
 	is eval("sub { \$a $c \$b $e \$c }"), undef, "$c $e non-associative";
 	is eval("sub { \$a $e \$b $c \$c }"), undef, "$e $c non-associative";
     }
 }
 foreach my $c (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $e0 (@cheqop) {
 	foreach my $e1 (@cheqop) {
 	    is eval("sub { \$a $c \$b $e0 \$c $e1 \$d }"), undef,