FWIW, the first two examples look correct to me.  An undefined Int should
stringify to `Int'; a defined Int should stringify in the obvious way.

Best regards,

Markus


msl@edward:~/perl/6$ ~/bin/perl6 -e 'my Int $x; $x.say'
Int
msl@edward:~/perl/6$ ~/bin/perl6 -e 'my Int $x = 42; $x.say'
42
msl@edward:~/perl/6$ ~/bin/perl6 -e 'my Int @a'
get_iter() not implemented in class 'Integer'
current instr.: '_block14' pc 97 (EVAL_7:57)
called from Sub 'parrot;PCT;HLLCompiler;eval' pc 892 (src/PCT/HLLCompiler.pir:508)
called from Sub 'parrot;PCT;HLLCompiler;command_line' pc 1436 (src/PCT/HLLCompiler.pir:768)
called from Sub 'parrot;Perl6;Compiler;main' pc 19057 (perl6.pir:162)
*** glibc detected *** /home/msl/bin/perl6: double free or corruption (!prev): 0x08455ec0 ***
======= Backtrace: =========
/lib/tls/i686/cmov/libc.so.6[0xb78077cd]
/lib/tls/i686/cmov/libc.so.6(cfree+0x90)[0xb780ae30]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(mem_sys_free+0x23)[0xb7bc2343]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bc2e3d]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd023f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_exit+0x70)[0xb7bb83e0]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bb7d46]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x61)[0xb7bb7db1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bb7fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7d18e26]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_default_get_iter+0x23)[0xb7d19de3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Object_get_iter+0x169)[0xb7e1ec39]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_instantiate+0x318)[0xb7dd7c88]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_new_p_p_p+0xa3)[0xb7b71043]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c00535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd2c09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd3723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd395c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bd40b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x1cc)[0xb7bb7f1c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bb7fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bf3b1a]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7dd5824]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_init_pmc+0x21f)[0xb7dd641f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(pmc_new_init+0x107)[0xb7bff1b7]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_newclass_p_p+0x58)[0xb7b717f8]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c00535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd2c09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd3723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd395c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bd40b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x1cc)[0xb7bb7f1c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bb7fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bf3b1a]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7dd5824]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_init_pmc+0x21f)[0xb7dd641f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(pmc_new_init+0x107)[0xb7bff1b7]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_newclass_p_p+0x58)[0xb7b717f8]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c00535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd2c09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd3723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bd395c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bd40b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runcode+0x269)[0xb7bb4519]
/home/msl/bin/perl6[0x8048a18]
/lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xdc)[0xb77b5ebc]
/home/msl/bin/perl6[0x8048851]
======= Memory map: ========
08048000-08263000 r-xp 00000000 08:01 8586467    /home/msl/parrot/languages/perl6/perl6
08263000-08264000 rw-p 0021a000 08:01 8586467    /home/msl/parrot/languages/perl6/perl6
08264000-086ea000 rw-p 08264000 00:00 0          [heap]
b6536000-b653b000 r--s 00000000 08:01 8539484    /home/msl/parrot/runtime/parrot/library/P6object.pbc
b663c000-b6669000 r--s 00000000 08:01 8539304    /home/msl/parrot/runtime/parrot/library/PGE.pbc
b6669000-b666b000 r--s 00000000 08:01 8539591    /home/msl/parrot/runtime/parrot/library/PCT/Grammar.pbc
b666b000-b666c000 r--s 00000000 08:01 8539589    /home/msl/parrot/runtime/parrot/library/PCT.pbc
b704b000-b7050000 r--s 00000000 08:01 8539478    /home/msl/parrot/runtime/parrot/library/Getopt/Obj.pbc
b7050000-b7073000 r--s 00000000 08:01 8539590    /home/msl/parrot/runtime/parrot/library/PCT/PAST.pbc
b7073000-b707a000 r-xp 00000000 08:01 8981757    /lib/tls/i686/cmov/librt-2.5.so
b707a000-b707c000 rw-p 00006000 08:01 8981757    /lib/tls/i686/cmov/librt-2.5.so
b7600000-b7621000 rw-p b7600000 00:00 0
b7621000-b7700000 ---p b7621000 00:00 0
b773b000-b7746000 r-xp 00000000 08:01 8978494    /lib/libgcc_s.so.1
b7746000-b7747000 rw-p 0000a000 08:01 8978494    /lib/libgcc_s.so.1
b775b000-b775c000 rw-p b775b000 00:00 0
b775c000-b7796000 r-xp 00000000 08:01 8978504    /lib/libncurses.so.5.5
b7796000-b779f000 rw-p 00039000 08:01 8978504    /lib/libncurses.so.5.5
b779f000-b77a0000 rw-p b779f000 00:00 0
b77a0000-b78db000 r-xp 00000000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b78db000-b78dc000 r--p 0013b000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b78dc000-b78de000 rw-p 0013c000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b78de000-b78e1000 rw-p b78de000 00:00 0
b78e1000-b790d000 r-xp 00000000 08:01 8978542    /lib/libreadline.so.5.2
b790d000-b7911000 rw-p 0002c000 08:01 8978542    /lib/libreadline.so.5.2
b7911000-b7912000 rw-p b7911000 00:00 0
b7912000-b7956000 r-xp 00000000 08:01 6883224    /usr/lib/libgmp.so.3.4.1
b7956000-b7957000 rw-p 00044000 08:01 6883224    /usr/lib/libgmp.so.3.4.1
b7957000-b795c000 r-xp 00000000 08:01 8981731    /lib/tls/i686/cmov/libcrypt-2.5.so
b795c000-b795e000 rw-p 00004000 08:01 8981731    /lib/tls/i686/cmov/libcrypt-2.5.so
b795e000-b7985000 rw-p b795e000 00:00 0
b7985000-b7998000 r-xp 00000000 08:01 8981753    /lib/tls/i686/cmov/libpthread-2.5.so
b7998000-b799a000 rw-p 00013000 08:01 8981753    /lib/tls/i686/cmov/libpthread-2.5.so
b799a000-b799c000 rw-p b799a000 00:00 0
b799c000-b79c1000 r-xp 00000000 08:01 8981735    /lib/tls/i686/cmov/libm-2.5.so
b79c1000-b79c3000 rw-p 00024000 08:01 8981735    /lib/tls/i686/cmov/libm-2.5.so
b79c3000-b79c4000 rw-p b79c3000 00:00 0
b79c4000-b79c6000 r-xp 00000000 08:01 8981733    /lib/tls/i686/cmov/libdl-2.5.so
b79c6000-b79c8000 rw-p 00001000 08:01 8981733    /lib/tls/i686/cmov/libdl-2.5.so
b79cb000-b79cd000 r--s 00000000 08:01 8539476    /home/msl/parrot/runtime/parrot/library/dumper.pbc
b79cd000-b79ce000 r--s 00000000 08:01 8539488    /home/msl/parrot/runtime/parrot/library/Parrot/Exception.pbc
b79ce000-b79d6000 r--s 00000000 08:01 8539592    /home/msl/parrot/runtime/parrot/library/PCT/HLLCompiler.pbc
b79d6000-b79d8000 r--s 00000000 08:01 8539493    /home/msl/parrot/runtime/parrot/library/PGE/Util.pbc
b79dc000-b7f6e000 r-xp 00000000 08:01 8538694    /home/msl/parrot/blib/lib/libparrot.so.0.8.2
b7f6e000-b7fb8000 rw-p 00591000 08:01 8538694    /home/msl/parrot/blib/lib/libparrot.so.0.8.2
b7fb8000-b7fba000 rw-p b7fb8000 00:00 0
b7fba000-b7fd3000 r-xp 00000000 08:01 8978453    /lib/ld-2.5.so
b7fd3000-b7fd5000 rw-p 00019000 08:01 8978453    /lib/ld-2.5.so
bf999000-bf9cd000 rw-p bf999000 00:00 0          [stack]
ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]
Aborted (core dumped)
msl@edward:~/perl/6$ ~/bin/perl6 -e 'my Int %h'
get_iter() not implemented in class 'Integer'
current instr.: '_block14' pc 97 (EVAL_7:57)
called from Sub 'parrot;PCT;HLLCompiler;eval' pc 892 (src/PCT/HLLCompiler.pir:508)
called from Sub 'parrot;PCT;HLLCompiler;command_line' pc 1436 (src/PCT/HLLCompiler.pir:768)
called from Sub 'parrot;Perl6;Compiler;main' pc 19057 (perl6.pir:162)
*** glibc detected *** /home/msl/bin/perl6: double free or corruption (!prev): 0x0836c740 ***
======= Backtrace: =========
/lib/tls/i686/cmov/libc.so.6[0xb78307cd]
/lib/tls/i686/cmov/libc.so.6(cfree+0x90)[0xb7833e30]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(mem_sys_free+0x23)[0xb7beb343]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bebe3d]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bf923f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_exit+0x70)[0xb7be13e0]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7be0d46]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x61)[0xb7be0db1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7be0fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7d41e26]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_default_get_iter+0x23)[0xb7d42de3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Object_get_iter+0x169)[0xb7e47c39]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_instantiate+0x318)[0xb7e00c88]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_new_p_p_p+0xa3)[0xb7b9a043]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c29535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfbc09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc95c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bfd0b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x1cc)[0xb7be0f1c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7be0fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c1cb1a]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7dfe824]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_init_pmc+0x21f)[0xb7dff41f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(pmc_new_init+0x107)[0xb7c281b7]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_newclass_p_p+0x58)[0xb7b9a7f8]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c29535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfbc09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc95c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bfd0b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_ex_throw_from_c+0x1cc)[0xb7be0f1c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7be0fb1]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c1cb1a]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7dfe824]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_Class_init_pmc+0x21f)[0xb7dff41f]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(pmc_new_init+0x107)[0xb7c281b7]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_newclass_p_p+0x58)[0xb7b9a7f8]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7c29535]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfbc09]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc723]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2[0xb7bfc95c]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runops_fromc_args+0x43)[0xb7bfd0b3]
/home/msl/parrot/blib/lib/libparrot.so.0.8.2(Parrot_runcode+0x269)[0xb7bdd519]
/home/msl/bin/perl6[0x8048a18]
/lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xdc)[0xb77deebc]
/home/msl/bin/perl6[0x8048851]
======= Memory map: ========
08048000-08263000 r-xp 00000000 08:01 8586467    /home/msl/parrot/languages/perl6/perl6
08263000-08264000 rw-p 0021a000 08:01 8586467    /home/msl/parrot/languages/perl6/perl6
08264000-086ec000 rw-p 08264000 00:00 0          [heap]
b655f000-b6564000 r--s 00000000 08:01 8539484    /home/msl/parrot/runtime/parrot/library/P6object.pbc
b6665000-b6692000 r--s 00000000 08:01 8539304    /home/msl/parrot/runtime/parrot/library/PGE.pbc
b6692000-b6694000 r--s 00000000 08:01 8539591    /home/msl/parrot/runtime/parrot/library/PCT/Grammar.pbc
b6694000-b6695000 r--s 00000000 08:01 8539589    /home/msl/parrot/runtime/parrot/library/PCT.pbc
b7074000-b7079000 r--s 00000000 08:01 8539478    /home/msl/parrot/runtime/parrot/library/Getopt/Obj.pbc
b7079000-b709c000 r--s 00000000 08:01 8539590    /home/msl/parrot/runtime/parrot/library/PCT/PAST.pbc
b709c000-b70a3000 r-xp 00000000 08:01 8981757    /lib/tls/i686/cmov/librt-2.5.so
b70a3000-b70a5000 rw-p 00006000 08:01 8981757    /lib/tls/i686/cmov/librt-2.5.so
b7600000-b7621000 rw-p b7600000 00:00 0
b7621000-b7700000 ---p b7621000 00:00 0
b7764000-b776f000 r-xp 00000000 08:01 8978494    /lib/libgcc_s.so.1
b776f000-b7770000 rw-p 0000a000 08:01 8978494    /lib/libgcc_s.so.1
b7784000-b7785000 rw-p b7784000 00:00 0
b7785000-b77bf000 r-xp 00000000 08:01 8978504    /lib/libncurses.so.5.5
b77bf000-b77c8000 rw-p 00039000 08:01 8978504    /lib/libncurses.so.5.5
b77c8000-b77c9000 rw-p b77c8000 00:00 0
b77c9000-b7904000 r-xp 00000000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b7904000-b7905000 r--p 0013b000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b7905000-b7907000 rw-p 0013c000 08:01 8981727    /lib/tls/i686/cmov/libc-2.5.so
b7907000-b790a000 rw-p b7907000 00:00 0
b790a000-b7936000 r-xp 00000000 08:01 8978542    /lib/libreadline.so.5.2
b7936000-b793a000 rw-p 0002c000 08:01 8978542    /lib/libreadline.so.5.2
b793a000-b793b000 rw-p b793a000 00:00 0
b793b000-b797f000 r-xp 00000000 08:01 6883224    /usr/lib/libgmp.so.3.4.1
b797f000-b7980000 rw-p 00044000 08:01 6883224    /usr/lib/libgmp.so.3.4.1
b7980000-b7985000 r-xp 00000000 08:01 8981731    /lib/tls/i686/cmov/libcrypt-2.5.so
b7985000-b7987000 rw-p 00004000 08:01 8981731    /lib/tls/i686/cmov/libcrypt-2.5.so
b7987000-b79ae000 rw-p b7987000 00:00 0
b79ae000-b79c1000 r-xp 00000000 08:01 8981753    /lib/tls/i686/cmov/libpthread-2.5.so
b79c1000-b79c3000 rw-p 00013000 08:01 8981753    /lib/tls/i686/cmov/libpthread-2.5.so
b79c3000-b79c5000 rw-p b79c3000 00:00 0
b79c5000-b79ea000 r-xp 00000000 08:01 8981735    /lib/tls/i686/cmov/libm-2.5.so
b79ea000-b79ec000 rw-p 00024000 08:01 8981735    /lib/tls/i686/cmov/libm-2.5.so
b79ec000-b79ed000 rw-p b79ec000 00:00 0
b79ed000-b79ef000 r-xp 00000000 08:01 8981733    /lib/tls/i686/cmov/libdl-2.5.so
b79ef000-b79f1000 rw-p 00001000 08:01 8981733    /lib/tls/i686/cmov/libdl-2.5.so
b79f4000-b79f6000 r--s 00000000 08:01 8539476    /home/msl/parrot/runtime/parrot/library/dumper.pbc
b79f6000-b79f7000 r--s 00000000 08:01 8539488    /home/msl/parrot/runtime/parrot/library/Parrot/Exception.pbc
b79f7000-b79ff000 r--s 00000000 08:01 8539592    /home/msl/parrot/runtime/parrot/library/PCT/HLLCompiler.pbc
b79ff000-b7a01000 r--s 00000000 08:01 8539493    /home/msl/parrot/runtime/parrot/library/PGE/Util.pbc
b7a05000-b7f97000 r-xp 00000000 08:01 8538694    /home/msl/parrot/blib/lib/libparrot.so.0.8.2
b7f97000-b7fe1000 rw-p 00591000 08:01 8538694    /home/msl/parrot/blib/lib/libparrot.so.0.8.2
b7fe1000-b7fe3000 rw-p b7fe1000 00:00 0
b7fe3000-b7ffc000 r-xp 00000000 08:01 8978453    /lib/ld-2.5.so
b7ffc000-b7ffe000 rw-p 00019000 08:01 8978453    /lib/ld-2.5.so
bf880000-bf8b1000 rw-p bf880000 00:00 0          [stack]
ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]
Aborted (core dumped)
msl@edward:~/perl/6$ uname -a
Linux edward 2.6.20-17-generic #2 SMP Wed Aug 20 16:47:34 UTC 2008 i686 GNU/Linux
msl@edward:~/perl/6$ gcc --version
gcc (GCC) 4.1.2 (Ubuntu 4.1.2-0ubuntu4)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

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