=head1 VERSION
-Version 0.01
+Version 0.02
=cut
our $VERSION;
BEGIN {
- $VERSION = '0.01';
+ $VERSION = '0.02';
}
=head1 SYNOPSIS
never returns C<1> argument but returns C<2> with probability C<1/2 * 1/2 = 1/4>, C<3> with probability C<1/2 * 1/2 + 1/2 * 1/2 = 1/2> and C<4> with probability C<1/4> too.
+=item * If a core function may return different numbers of scalars, each kind is considered equally possible.
+
+For example, C<stat> returns C<13> elements on success and C<0> on error. The according probability will then be C<< { 0 => 0.5, 13 => 0.5 } >>.
+
=item * The C<list> state is absorbing in regard of all the other ones.
This is just a pedantic way to say that "list + fixed length = list".
}} map { (ref) ? $_ : { $_ => 1 } } grep defined, @_;
}
+sub power {
+ my ($p, $n, $c) = @_;
+ my $s = sum values %$p;
+ return { 0 => $s * $c } unless $n;
+ if ($n eq 'list') {
+ my $z = delete $p->{0};
+ return { 'list' => $c } unless $z;
+ return { 0 => $c } if $z == 1;
+ return { 0 => $c * $z, list => $c * ($s - $z) };
+ }
+ my $r = combine map { { %$p } } 1 .. $n;
+ $r->{$_} *= $c for keys %$r;
+ return $r;
+}
+
sub add {
reduce {
$a->{$_} += $b->{$_} for keys %$b;
$ops{$_} = 1 for qw/padsv/;
$ops{$_} = 'list' for qw/padav/;
$ops{$_} = 'list' for qw/padhv rv2hv/;
-$ops{$_} = 'list' for qw/padany flip match entereval readline/;
+$ops{$_} = 'list' for qw/padany/;
+$ops{$_} = 'list' for qw/match entereval readline/;
$ops{each} = { 0 => 0.5, 2 => 0.5 };
$ops{stat} = { 0 => 0.5, 13 => 0.5 };
sub expect_return {
my ($self, $op) = @_;
- return ($self->expect_list($op))[0] => 1 if name($op) eq 'return';
+ return ($self->expect_kids($op))[0] => 1 if name($op) eq 'return';
if ($op->flags & OPf_KIDS) {
for ($op = $op->first; not null $op; $op = $op->sibling) {
}
}
- return;
+ return 0;
}
-sub expect_list {
+sub expect_any {
my ($self, $op) = @_;
my $n = name($op);
+ return ($self->expect_kids($op))[0] => 1 if $n eq 'return';
+
my $meth = $self->can('pp_' . $n);
return $self->$meth($op) if $meth;
+
if (exists $ops{$n}) {
my $r = $ops{$n};
- $r = { %$r } if ref $r eq 'HASH';
+ $r = { %$r } if ref $r;
return $r => 0;
}
- if ($op->flags & OPf_KIDS) {
- my @res = (0);
- my ($p, $r);
- for ($op = $op->first; not null $op; $op = $op->sibling) {
- my $n = name($op);
- next if $n eq 'pushmark';
- if ($n eq 'nextstate'
- and not null(($op = $op->sibling)->sibling)) {
- ($p, $r) = $self->expect_return($op);
- return $p => 1 if $r;
- } else {
- ($p, $r) = $self->expect_any($op);
- return $p => 1 if $r;
- push @res, $p;
- }
- }
- return (combine @res) => 0;
- }
-
- return;
-}
-
-sub expect_any {
- my ($self, $op) = @_;
-
- return ($self->expect_list($op))[0] => 1 if name($op) eq 'return';
-
if (class($op) eq 'LOGOP' and not null $op->first) {
my @res;
my ($p, $r);
return (add @res) => 0;
}
- return $self->expect_list($op);
+ return $self->expect_kids($op);
+}
+
+sub expect_kids {
+ my ($self, $op) = @_;
+
+ return 0 unless $op->flags & OPf_KIDS;
+
+ my @res = (0);
+ my ($p, $r);
+ for ($op = $op->first; not null $op; $op = $op->sibling) {
+ my $n = name($op);
+ next if $n eq 'pushmark';
+ if ($n eq 'nextstate'
+ and not null(($op = $op->sibling)->sibling)) {
+ ($p, $r) = $self->expect_return($op);
+ return $p => 1 if $r;
+ } else {
+ ($p, $r) = $self->expect_any($op);
+ return $p => 1 if $r;
+ push @res, $p;
+ }
+ }
+
+ return (combine @res) => 0;
}
# Stolen from B::Deparse
sub pp_const {
my ($self, $op) = @_;
- if (class($op) eq 'SVOP' and (my $sv = $self->const_sv($op))) {
- my $c = class($sv);
- if ($c eq 'AV') {
- return $sv->FILL + 1;
- } elsif ($c eq 'HV') {
- return 2 * $sv->FILL;
- }
+ my $sv = $self->const_sv($op);
+ my $c = class($sv);
+ if ($c eq 'AV') {
+ return $sv->FILL + 1;
+ } elsif ($c eq 'HV') {
+ return 2 * $sv->FILL;
}
return 1;
return (name($op) eq 'const') ? $self->expect_any($op) : 'list';
}
-sub pp_aassign { $_[0]->expect_any($_[1]->first) }
+sub pp_aassign {
+ my ($self, $op) = @_;
+
+ $op = $op->first;
+
+ # Can't assign to return
+ my ($p, $r) = $self->expect_any($op->sibling);
+ return $p => 0 if not exists $p->{list};
+
+ $self->expect_any($op);
+}
sub pp_leaveloop { $_[0]->expect_return($_[1]->first->sibling) }
+sub pp_flip {
+ my ($self, $op) = @_;
+
+ $op = $op->first;
+ return 'list' if name($op) ne 'range';
+
+ my $begin = $op->first;
+ if (name($begin) eq 'const') {
+ my $end = $begin->sibling;
+ if (name($end) eq 'const') {
+ $begin = $self->const_sv($begin);
+ $end = $self->const_sv($end);
+ no warnings 'numeric';
+ return int(${$end->object_2svref}) - int(${$begin->object_2svref}) + 1;
+ } else {
+ my ($p, $r) = $self->expect_return($end);
+ return $p => 1 if $r;
+ }
+ } else {
+ my ($p, $r) = $self->expect_return($begin);
+ return $p => 1 if $r;
+ }
+
+ return 'list'
+}
+
+sub pp_grepwhile {
+ my ($self, $op) = @_;
+
+ $op = $op->first;
+ return 'list' if name($op) ne 'grepstart';
+
+ $op = $op->first->sibling;
+ my ($p, $r) = $self->expect_any($op);
+ return $p => 1 if $r;
+
+ $op = $op->sibling;
+ ($p, $r) = $self->expect_any($op);
+ return $p => 1 if $r;
+
+ return 'list';
+}
+
+sub pp_mapwhile {
+ my ($self, $op) = @_;
+
+ $op = $op->first;
+ return 'list' if name($op) ne 'mapstart';
+
+ $op = $op->first->sibling;
+ my ($p1, $r) = $self->expect_any($op);
+ return $p1 => 1 if $r;
+
+ $op = $op->sibling;
+ (my $p2, $r) = $self->expect_any($op);
+ return $p2 => 1 if $r;
+ $p2 = { $p2 => 1 } unless ref $p2;
+
+ return add map { power $p1, $_, $p2->{$_} } keys %$p2;
+}
+
=head1 EXPORT
An object-oriented module shouldn't export any function, and so does this one.
projects / perl / modules / Sub-Nary.git / blobdiff