From @ilyabelikin

Hi,
look like bug (in r31017)​:

my $k = 'bar';
my %s;
say defined $k; # 1
say defined %s{$k}; # 0
say defined $k and defined %s{$k}; # 1 (!) must be 0
say 1 && 0; # 0

Ilya
Vladivostok.pm

From @bacek

Hello.

This is parsing bug.

"say defined $a and defined %b{$a}" parsed as "(say defined $a) and
defined %b{$a}"

--
Bacek.

The RT System itself - Status changed from 'new' to 'open'

From @masak

Ilya (>)​:

look like bug (in r31017)​:

my $k = 'bar';
my %s;
say defined $k; # 1
say defined %s{$k}; # 0
say defined $k and defined %s{$k}; # 1 (!) must be 0
say 1 && 0; # 0

No, this is intended. "and" has very loose precedence, even looser
than the "say" call. The crucial statement is thus parsed like this​:

(say defined $k) and defined %s{$k};

...which would output 1 but return 0.

To learn more about operator precedence, see

<http://perlcabal.org/syn/S03.html#Operator_precedence>

Also check out the excellent "perldoc perlop" for Perl 5 for more
examples of this.

<http://perldoc.perl.org/perlop.html>

// Carl

From @ilyabelikin

Hi,
thank you. Do we have ticket for this parsing bug?
I have serched for it, bot do not find.

2008/9/14 via RT Ilya Belikin <perl6-bugs-followup@​perl.org>​:

# New Ticket Created by Ilya Belikin
# Please include the string​: [perl #​58830]
# in the subject line of all future correspondence about this issue.
# <URL​: http://rt.perl.org/rt3/Ticket/Display.html?id=58830 >

Hi,
look like bug (in r31017)​:

my $k = 'bar';
my %s;
say defined $k; # 1
say defined %s{$k}; # 0
say defined $k and defined %s{$k}; # 1 (!) must be 0
say 1 && 0; # 0

Ilya
Vladivostok.pm

From @bacek

Ilya Belikin wrote​:

Hi,
look like bug (in r31017)​:

my $k = 'bar';
my %s;
say defined $k; # 1
say defined %s{$k}; # 0
say defined $k and defined %s{$k}; # 1 (!) must be 0
say 1 && 0; # 0

I replyed in ticket, but it doesn't hit mailinglist. This is bug in
parsing. "say defined $k and defined %s{$k};" parsed as "(say defined
$k) and defined %s{$k};"

--
Bacek

From @pmichaud

On Sun, Sep 14, 2008 at 09​:13​:33PM +1000, Vasily Chekalkin wrote​:

Ilya Belikin wrote​:

Hi,
look like bug (in r31017)​:

my $k = 'bar';
my %s;
say defined $k; # 1
say defined %s{$k}; # 0
say defined $k and defined %s{$k}; # 1 (!) must be 0
say 1 && 0; # 0

I replyed in ticket, but it doesn't hit mailinglist. This is bug in
parsing. "say defined $k and defined %s{$k};" parsed as "(say defined
$k) and defined %s{$k};"

As Carl correctly noted, Rakudo has the parsing for infix​:<and> correct --
infix​:<and> has looser precedence than listops (including 'say'), so
Rakudo is doing the right thing here.

The intended version is likely​:

  say defined $k && defined %s{$k};

However, as of r31017 Rakudo did not have 'defined' as a named
unary, so parsed this version as

  say( defined( $k && defined( %s{$k} ) ) );

which is also not what is wanted. In r31116 I've changed 'defined'
to be a named unary, and we now get the desired output​:

  $ cat x
  my $k = 'bar';
  my %s;
  say defined $k; # 1
  say defined %s{$k}; # 0
  say defined $k and defined %s{$k}; # 1
  say defined $k && defined %s{$k}; # 0
  $ ./parrot perl6.pbc x
  1
  0
  1
  0

We probably need to test that 'defined' is a named unary in t/spec.

Closing ticket, thanks.

Pm

@pmichaud - Status changed from 'open' to 'resolved'