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Diffstat (limited to 'Master/tlpkg/tlperl/lib/Data/Dumper.pm')
| -rwxr-xr-x | Master/tlpkg/tlperl/lib/Data/Dumper.pm | 1306 |
1 files changed, 1306 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl/lib/Data/Dumper.pm b/Master/tlpkg/tlperl/lib/Data/Dumper.pm new file mode 100755 index 00000000000..0eb8bf74fd6 --- /dev/null +++ b/Master/tlpkg/tlperl/lib/Data/Dumper.pm @@ -0,0 +1,1306 @@ +# +# Data/Dumper.pm +# +# convert perl data structures into perl syntax suitable for both printing +# and eval +# +# Documentation at the __END__ +# + +package Data::Dumper; + +$VERSION = '2.125'; # Don't forget to set version and release date in POD! + +#$| = 1; + +use 5.006_001; +require Exporter; +require overload; + +use Carp; + +BEGIN { + @ISA = qw(Exporter); + @EXPORT = qw(Dumper); + @EXPORT_OK = qw(DumperX); + + # if run under miniperl, or otherwise lacking dynamic loading, + # XSLoader should be attempted to load, or the pure perl flag + # toggled on load failure. + eval { + require XSLoader; + }; + $Useperl = 1 if $@; +} + +XSLoader::load( 'Data::Dumper' ) unless $Useperl; + +# module vars and their defaults +$Indent = 2 unless defined $Indent; +$Purity = 0 unless defined $Purity; +$Pad = "" unless defined $Pad; +$Varname = "VAR" unless defined $Varname; +$Useqq = 0 unless defined $Useqq; +$Terse = 0 unless defined $Terse; +$Freezer = "" unless defined $Freezer; +$Toaster = "" unless defined $Toaster; +$Deepcopy = 0 unless defined $Deepcopy; +$Quotekeys = 1 unless defined $Quotekeys; +$Bless = "bless" unless defined $Bless; +#$Expdepth = 0 unless defined $Expdepth; +$Maxdepth = 0 unless defined $Maxdepth; +$Pair = ' => ' unless defined $Pair; +$Useperl = 0 unless defined $Useperl; +$Sortkeys = 0 unless defined $Sortkeys; +$Deparse = 0 unless defined $Deparse; + +# +# expects an arrayref of values to be dumped. +# can optionally pass an arrayref of names for the values. +# names must have leading $ sign stripped. begin the name with * +# to cause output of arrays and hashes rather than refs. +# +sub new { + my($c, $v, $n) = @_; + + croak "Usage: PACKAGE->new(ARRAYREF, [ARRAYREF])" + unless (defined($v) && (ref($v) eq 'ARRAY')); + $n = [] unless (defined($n) && (ref($n) eq 'ARRAY')); + + my($s) = { + level => 0, # current recursive depth + indent => $Indent, # various styles of indenting + pad => $Pad, # all lines prefixed by this string + xpad => "", # padding-per-level + apad => "", # added padding for hash keys n such + sep => "", # list separator + pair => $Pair, # hash key/value separator: defaults to ' => ' + seen => {}, # local (nested) refs (id => [name, val]) + todump => $v, # values to dump [] + names => $n, # optional names for values [] + varname => $Varname, # prefix to use for tagging nameless ones + purity => $Purity, # degree to which output is evalable + useqq => $Useqq, # use "" for strings (backslashitis ensues) + terse => $Terse, # avoid name output (where feasible) + freezer => $Freezer, # name of Freezer method for objects + toaster => $Toaster, # name of method to revive objects + deepcopy => $Deepcopy, # dont cross-ref, except to stop recursion + quotekeys => $Quotekeys, # quote hash keys + 'bless' => $Bless, # keyword to use for "bless" +# expdepth => $Expdepth, # cutoff depth for explicit dumping + maxdepth => $Maxdepth, # depth beyond which we give up + useperl => $Useperl, # use the pure Perl implementation + sortkeys => $Sortkeys, # flag or filter for sorting hash keys + deparse => $Deparse, # use B::Deparse for coderefs + }; + + if ($Indent > 0) { + $s->{xpad} = " "; + $s->{sep} = "\n"; + } + return bless($s, $c); +} + +if ($] >= 5.008) { + # Packed numeric addresses take less memory. Plus pack is faster than sprintf + *init_refaddr_format = sub {}; + + *format_refaddr = sub { + require Scalar::Util; + pack "J", Scalar::Util::refaddr(shift); + }; +} else { + *init_refaddr_format = sub { + require Config; + my $f = $Config::Config{uvxformat}; + $f =~ tr/"//d; + our $refaddr_format = "0x%" . $f; + }; + + *format_refaddr = sub { + require Scalar::Util; + sprintf our $refaddr_format, Scalar::Util::refaddr(shift); + } +} + +# +# add-to or query the table of already seen references +# +sub Seen { + my($s, $g) = @_; + if (defined($g) && (ref($g) eq 'HASH')) { + init_refaddr_format(); + my($k, $v, $id); + while (($k, $v) = each %$g) { + if (defined $v and ref $v) { + $id = format_refaddr($v); + if ($k =~ /^[*](.*)$/) { + $k = (ref $v eq 'ARRAY') ? ( "\\\@" . $1 ) : + (ref $v eq 'HASH') ? ( "\\\%" . $1 ) : + (ref $v eq 'CODE') ? ( "\\\&" . $1 ) : + ( "\$" . $1 ) ; + } + elsif ($k !~ /^\$/) { + $k = "\$" . $k; + } + $s->{seen}{$id} = [$k, $v]; + } + else { + carp "Only refs supported, ignoring non-ref item \$$k"; + } + } + return $s; + } + else { + return map { @$_ } values %{$s->{seen}}; + } +} + +# +# set or query the values to be dumped +# +sub Values { + my($s, $v) = @_; + if (defined($v) && (ref($v) eq 'ARRAY')) { + $s->{todump} = [@$v]; # make a copy + return $s; + } + else { + return @{$s->{todump}}; + } +} + +# +# set or query the names of the values to be dumped +# +sub Names { + my($s, $n) = @_; + if (defined($n) && (ref($n) eq 'ARRAY')) { + $s->{names} = [@$n]; # make a copy + return $s; + } + else { + return @{$s->{names}}; + } +} + +sub DESTROY {} + +sub Dump { + return &Dumpxs + unless $Data::Dumper::Useperl || (ref($_[0]) && $_[0]->{useperl}) || + $Data::Dumper::Useqq || (ref($_[0]) && $_[0]->{useqq}) || + $Data::Dumper::Deparse || (ref($_[0]) && $_[0]->{deparse}); + return &Dumpperl; +} + +# +# dump the refs in the current dumper object. +# expects same args as new() if called via package name. +# +sub Dumpperl { + my($s) = shift; + my(@out, $val, $name); + my($i) = 0; + local(@post); + init_refaddr_format(); + + $s = $s->new(@_) unless ref $s; + + for $val (@{$s->{todump}}) { + my $out = ""; + @post = (); + $name = $s->{names}[$i++]; + if (defined $name) { + if ($name =~ /^[*](.*)$/) { + if (defined $val) { + $name = (ref $val eq 'ARRAY') ? ( "\@" . $1 ) : + (ref $val eq 'HASH') ? ( "\%" . $1 ) : + (ref $val eq 'CODE') ? ( "\*" . $1 ) : + ( "\$" . $1 ) ; + } + else { + $name = "\$" . $1; + } + } + elsif ($name !~ /^\$/) { + $name = "\$" . $name; + } + } + else { + $name = "\$" . $s->{varname} . $i; + } + + my $valstr; + { + local($s->{apad}) = $s->{apad}; + $s->{apad} .= ' ' x (length($name) + 3) if $s->{indent} >= 2; + $valstr = $s->_dump($val, $name); + } + + $valstr = "$name = " . $valstr . ';' if @post or !$s->{terse}; + $out .= $s->{pad} . $valstr . $s->{sep}; + $out .= $s->{pad} . join(';' . $s->{sep} . $s->{pad}, @post) + . ';' . $s->{sep} if @post; + + push @out, $out; + } + return wantarray ? @out : join('', @out); +} + +# wrap string in single quotes (escaping if needed) +sub _quote { + my $val = shift; + $val =~ s/([\\\'])/\\$1/g; + return "'" . $val . "'"; +} + +# +# twist, toil and turn; +# and recurse, of course. +# sometimes sordidly; +# and curse if no recourse. +# +sub _dump { + my($s, $val, $name) = @_; + my($sname); + my($out, $realpack, $realtype, $type, $ipad, $id, $blesspad); + + $type = ref $val; + $out = ""; + + if ($type) { + + # Call the freezer method if it's specified and the object has the + # method. Trap errors and warn() instead of die()ing, like the XS + # implementation. + my $freezer = $s->{freezer}; + if ($freezer and UNIVERSAL::can($val, $freezer)) { + eval { $val->$freezer() }; + warn "WARNING(Freezer method call failed): $@" if $@; + } + + require Scalar::Util; + $realpack = Scalar::Util::blessed($val); + $realtype = $realpack ? Scalar::Util::reftype($val) : ref $val; + $id = format_refaddr($val); + + # if it has a name, we need to either look it up, or keep a tab + # on it so we know when we hit it later + if (defined($name) and length($name)) { + # keep a tab on it so that we dont fall into recursive pit + if (exists $s->{seen}{$id}) { +# if ($s->{expdepth} < $s->{level}) { + if ($s->{purity} and $s->{level} > 0) { + $out = ($realtype eq 'HASH') ? '{}' : + ($realtype eq 'ARRAY') ? '[]' : + 'do{my $o}' ; + push @post, $name . " = " . $s->{seen}{$id}[0]; + } + else { + $out = $s->{seen}{$id}[0]; + if ($name =~ /^([\@\%])/) { + my $start = $1; + if ($out =~ /^\\$start/) { + $out = substr($out, 1); + } + else { + $out = $start . '{' . $out . '}'; + } + } + } + return $out; +# } + } + else { + # store our name + $s->{seen}{$id} = [ (($name =~ /^[@%]/) ? ('\\' . $name ) : + ($realtype eq 'CODE' and + $name =~ /^[*](.*)$/) ? ('\\&' . $1 ) : + $name ), + $val ]; + } + } + my $no_bless = 0; + my $is_regex = 0; + if ( $realpack and ($] >= 5.009005 ? re::is_regexp($val) : $realpack eq 'Regexp') ) { + $is_regex = 1; + $no_bless = $realpack eq 'Regexp'; + } + + # If purity is not set and maxdepth is set, then check depth: + # if we have reached maximum depth, return the string + # representation of the thing we are currently examining + # at this depth (i.e., 'Foo=ARRAY(0xdeadbeef)'). + if (!$s->{purity} + and $s->{maxdepth} > 0 + and $s->{level} >= $s->{maxdepth}) + { + return qq['$val']; + } + + # we have a blessed ref + if ($realpack and !$no_bless) { + $out = $s->{'bless'} . '( '; + $blesspad = $s->{apad}; + $s->{apad} .= ' ' if ($s->{indent} >= 2); + } + + $s->{level}++; + $ipad = $s->{xpad} x $s->{level}; + + if ($is_regex) { + my $pat; + # This really sucks, re:regexp_pattern is in ext/re/re.xs and not in + # universal.c, and even worse we cant just require that re to be loaded + # we *have* to use() it. + # We should probably move it to universal.c for 5.10.1 and fix this. + # Currently we only use re::regexp_pattern when the re is blessed into another + # package. This has the disadvantage of meaning that a DD dump won't round trip + # as the pattern will be repeatedly wrapped with the same modifiers. + # This is an aesthetic issue so we will leave it for now, but we could use + # regexp_pattern() in list context to get the modifiers separately. + # But since this means loading the full debugging engine in process we wont + # bother unless its necessary for accuracy. + if (($realpack ne 'Regexp') && defined(*re::regexp_pattern{CODE})) { + $pat = re::regexp_pattern($val); + } else { + $pat = "$val"; + } + $pat =~ s,/,\\/,g; + $out .= "qr/$pat/"; + } + elsif ($realtype eq 'SCALAR' || $realtype eq 'REF') { + if ($realpack) { + $out .= 'do{\\(my $o = ' . $s->_dump($$val, "\${$name}") . ')}'; + } + else { + $out .= '\\' . $s->_dump($$val, "\${$name}"); + } + } + elsif ($realtype eq 'GLOB') { + $out .= '\\' . $s->_dump($$val, "*{$name}"); + } + elsif ($realtype eq 'ARRAY') { + my($pad, $mname); + my($i) = 0; + $out .= ($name =~ /^\@/) ? '(' : '['; + $pad = $s->{sep} . $s->{pad} . $s->{apad}; + ($name =~ /^\@(.*)$/) ? ($mname = "\$" . $1) : + # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar} + ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) : + ($mname = $name . '->'); + $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/; + for my $v (@$val) { + $sname = $mname . '[' . $i . ']'; + $out .= $pad . $ipad . '#' . $i if $s->{indent} >= 3; + $out .= $pad . $ipad . $s->_dump($v, $sname); + $out .= "," if $i++ < $#$val; + } + $out .= $pad . ($s->{xpad} x ($s->{level} - 1)) if $i; + $out .= ($name =~ /^\@/) ? ')' : ']'; + } + elsif ($realtype eq 'HASH') { + my($k, $v, $pad, $lpad, $mname, $pair); + $out .= ($name =~ /^\%/) ? '(' : '{'; + $pad = $s->{sep} . $s->{pad} . $s->{apad}; + $lpad = $s->{apad}; + $pair = $s->{pair}; + ($name =~ /^\%(.*)$/) ? ($mname = "\$" . $1) : + # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar} + ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) : + ($mname = $name . '->'); + $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/; + my ($sortkeys, $keys, $key) = ("$s->{sortkeys}"); + if ($sortkeys) { + if (ref($s->{sortkeys}) eq 'CODE') { + $keys = $s->{sortkeys}($val); + unless (ref($keys) eq 'ARRAY') { + carp "Sortkeys subroutine did not return ARRAYREF"; + $keys = []; + } + } + else { + $keys = [ sort keys %$val ]; + } + } + + # Ensure hash iterator is reset + keys(%$val); + + while (($k, $v) = ! $sortkeys ? (each %$val) : + @$keys ? ($key = shift(@$keys), $val->{$key}) : + () ) + { + my $nk = $s->_dump($k, ""); + $nk = $1 if !$s->{quotekeys} and $nk =~ /^[\"\']([A-Za-z_]\w*)[\"\']$/; + $sname = $mname . '{' . $nk . '}'; + $out .= $pad . $ipad . $nk . $pair; + + # temporarily alter apad + $s->{apad} .= (" " x (length($nk) + 4)) if $s->{indent} >= 2; + $out .= $s->_dump($val->{$k}, $sname) . ","; + $s->{apad} = $lpad if $s->{indent} >= 2; + } + if (substr($out, -1) eq ',') { + chop $out; + $out .= $pad . ($s->{xpad} x ($s->{level} - 1)); + } + $out .= ($name =~ /^\%/) ? ')' : '}'; + } + elsif ($realtype eq 'CODE') { + if ($s->{deparse}) { + require B::Deparse; + my $sub = 'sub ' . (B::Deparse->new)->coderef2text($val); + $pad = $s->{sep} . $s->{pad} . $s->{apad} . $s->{xpad} x ($s->{level} - 1); + $sub =~ s/\n/$pad/gse; + $out .= $sub; + } else { + $out .= 'sub { "DUMMY" }'; + carp "Encountered CODE ref, using dummy placeholder" if $s->{purity}; + } + } + else { + croak "Can\'t handle $realtype type."; + } + + if ($realpack and !$no_bless) { # we have a blessed ref + $out .= ', ' . _quote($realpack) . ' )'; + $out .= '->' . $s->{toaster} . '()' if $s->{toaster} ne ''; + $s->{apad} = $blesspad; + } + $s->{level}--; + + } + else { # simple scalar + + my $ref = \$_[1]; + # first, catalog the scalar + if ($name ne '') { + $id = format_refaddr($ref); + if (exists $s->{seen}{$id}) { + if ($s->{seen}{$id}[2]) { + $out = $s->{seen}{$id}[0]; + #warn "[<$out]\n"; + return "\${$out}"; + } + } + else { + #warn "[>\\$name]\n"; + $s->{seen}{$id} = ["\\$name", $ref]; + } + } + if (ref($ref) eq 'GLOB' or "$ref" =~ /=GLOB\([^()]+\)$/) { # glob + my $name = substr($val, 1); + if ($name =~ /^[A-Za-z_][\w:]*$/) { + $name =~ s/^main::/::/; + $sname = $name; + } + else { + $sname = $s->_dump($name, ""); + $sname = '{' . $sname . '}'; + } + if ($s->{purity}) { + my $k; + local ($s->{level}) = 0; + for $k (qw(SCALAR ARRAY HASH)) { + my $gval = *$val{$k}; + next unless defined $gval; + next if $k eq "SCALAR" && ! defined $$gval; # always there + + # _dump can push into @post, so we hold our place using $postlen + my $postlen = scalar @post; + $post[$postlen] = "\*$sname = "; + local ($s->{apad}) = " " x length($post[$postlen]) if $s->{indent} >= 2; + $post[$postlen] .= $s->_dump($gval, "\*$sname\{$k\}"); + } + } + $out .= '*' . $sname; + } + elsif (!defined($val)) { + $out .= "undef"; + } + elsif ($val =~ /^(?:0|-?[1-9]\d{0,8})\z/) { # safe decimal number + $out .= $val; + } + else { # string + if ($s->{useqq} or $val =~ tr/\0-\377//c) { + # Fall back to qq if there's Unicode + $out .= qquote($val, $s->{useqq}); + } + else { + $out .= _quote($val); + } + } + } + if ($id) { + # if we made it this far, $id was added to seen list at current + # level, so remove it to get deep copies + if ($s->{deepcopy}) { + delete($s->{seen}{$id}); + } + elsif ($name) { + $s->{seen}{$id}[2] = 1; + } + } + return $out; +} + +# +# non-OO style of earlier version +# +sub Dumper { + return Data::Dumper->Dump([@_]); +} + +# compat stub +sub DumperX { + return Data::Dumper->Dumpxs([@_], []); +} + +sub Dumpf { return Data::Dumper->Dump(@_) } + +sub Dumpp { print Data::Dumper->Dump(@_) } + +# +# reset the "seen" cache +# +sub Reset { + my($s) = shift; + $s->{seen} = {}; + return $s; +} + +sub Indent { + my($s, $v) = @_; + if (defined($v)) { + if ($v == 0) { + $s->{xpad} = ""; + $s->{sep} = ""; + } + else { + $s->{xpad} = " "; + $s->{sep} = "\n"; + } + $s->{indent} = $v; + return $s; + } + else { + return $s->{indent}; + } +} + +sub Pair { + my($s, $v) = @_; + defined($v) ? (($s->{pair} = $v), return $s) : $s->{pair}; +} + +sub Pad { + my($s, $v) = @_; + defined($v) ? (($s->{pad} = $v), return $s) : $s->{pad}; +} + +sub Varname { + my($s, $v) = @_; + defined($v) ? (($s->{varname} = $v), return $s) : $s->{varname}; +} + +sub Purity { + my($s, $v) = @_; + defined($v) ? (($s->{purity} = $v), return $s) : $s->{purity}; +} + +sub Useqq { + my($s, $v) = @_; + defined($v) ? (($s->{useqq} = $v), return $s) : $s->{useqq}; +} + +sub Terse { + my($s, $v) = @_; + defined($v) ? (($s->{terse} = $v), return $s) : $s->{terse}; +} + +sub Freezer { + my($s, $v) = @_; + defined($v) ? (($s->{freezer} = $v), return $s) : $s->{freezer}; +} + +sub Toaster { + my($s, $v) = @_; + defined($v) ? (($s->{toaster} = $v), return $s) : $s->{toaster}; +} + +sub Deepcopy { + my($s, $v) = @_; + defined($v) ? (($s->{deepcopy} = $v), return $s) : $s->{deepcopy}; +} + +sub Quotekeys { + my($s, $v) = @_; + defined($v) ? (($s->{quotekeys} = $v), return $s) : $s->{quotekeys}; +} + +sub Bless { + my($s, $v) = @_; + defined($v) ? (($s->{'bless'} = $v), return $s) : $s->{'bless'}; +} + +sub Maxdepth { + my($s, $v) = @_; + defined($v) ? (($s->{'maxdepth'} = $v), return $s) : $s->{'maxdepth'}; +} + +sub Useperl { + my($s, $v) = @_; + defined($v) ? (($s->{'useperl'} = $v), return $s) : $s->{'useperl'}; +} + +sub Sortkeys { + my($s, $v) = @_; + defined($v) ? (($s->{'sortkeys'} = $v), return $s) : $s->{'sortkeys'}; +} + +sub Deparse { + my($s, $v) = @_; + defined($v) ? (($s->{'deparse'} = $v), return $s) : $s->{'deparse'}; +} + +# used by qquote below +my %esc = ( + "\a" => "\\a", + "\b" => "\\b", + "\t" => "\\t", + "\n" => "\\n", + "\f" => "\\f", + "\r" => "\\r", + "\e" => "\\e", +); + +# put a string value in double quotes +sub qquote { + local($_) = shift; + s/([\\\"\@\$])/\\$1/g; + my $bytes; { use bytes; $bytes = length } + s/([^\x00-\x7f])/'\x{'.sprintf("%x",ord($1)).'}'/ge if $bytes > length; + return qq("$_") unless + /[^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; # fast exit + + my $high = shift || ""; + s/([\a\b\t\n\f\r\e])/$esc{$1}/g; + + if (ord('^')==94) { # ascii + # no need for 3 digits in escape for these + s/([\0-\037])(?!\d)/'\\'.sprintf('%o',ord($1))/eg; + s/([\0-\037\177])/'\\'.sprintf('%03o',ord($1))/eg; + # all but last branch below not supported --BEHAVIOR SUBJECT TO CHANGE-- + if ($high eq "iso8859") { + s/([\200-\240])/'\\'.sprintf('%o',ord($1))/eg; + } elsif ($high eq "utf8") { +# use utf8; +# $str =~ s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge; + } elsif ($high eq "8bit") { + # leave it as it is + } else { + s/([\200-\377])/'\\'.sprintf('%03o',ord($1))/eg; + s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge; + } + } + else { # ebcdic + s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])(?!\d)} + {my $v = ord($1); '\\'.sprintf(($v <= 037 ? '%o' : '%03o'), $v)}eg; + s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])} + {'\\'.sprintf('%03o',ord($1))}eg; + } + + return qq("$_"); +} + +# helper sub to sort hash keys in Perl < 5.8.0 where we don't have +# access to sortsv() from XS +sub _sortkeys { [ sort keys %{$_[0]} ] } + +1; +__END__ + +=head1 NAME + +Data::Dumper - stringified perl data structures, suitable for both printing and C<eval> + +=head1 SYNOPSIS + + use Data::Dumper; + + # simple procedural interface + print Dumper($foo, $bar); + + # extended usage with names + print Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]); + + # configuration variables + { + local $Data::Dumper::Purity = 1; + eval Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]); + } + + # OO usage + $d = Data::Dumper->new([$foo, $bar], [qw(foo *ary)]); + ... + print $d->Dump; + ... + $d->Purity(1)->Terse(1)->Deepcopy(1); + eval $d->Dump; + + +=head1 DESCRIPTION + +Given a list of scalars or reference variables, writes out their contents in +perl syntax. The references can also be objects. The content of each +variable is output in a single Perl statement. Handles self-referential +structures correctly. + +The return value can be C<eval>ed to get back an identical copy of the +original reference structure. + +Any references that are the same as one of those passed in will be named +C<$VAR>I<n> (where I<n> is a numeric suffix), and other duplicate references +to substructures within C<$VAR>I<n> will be appropriately labeled using arrow +notation. You can specify names for individual values to be dumped if you +use the C<Dump()> method, or you can change the default C<$VAR> prefix to +something else. See C<$Data::Dumper::Varname> and C<$Data::Dumper::Terse> +below. + +The default output of self-referential structures can be C<eval>ed, but the +nested references to C<$VAR>I<n> will be undefined, since a recursive +structure cannot be constructed using one Perl statement. You should set the +C<Purity> flag to 1 to get additional statements that will correctly fill in +these references. Moreover, if C<eval>ed when strictures are in effect, +you need to ensure that any variables it accesses are previously declared. + +In the extended usage form, the references to be dumped can be given +user-specified names. If a name begins with a C<*>, the output will +describe the dereferenced type of the supplied reference for hashes and +arrays, and coderefs. Output of names will be avoided where possible if +the C<Terse> flag is set. + +In many cases, methods that are used to set the internal state of the +object will return the object itself, so method calls can be conveniently +chained together. + +Several styles of output are possible, all controlled by setting +the C<Indent> flag. See L<Configuration Variables or Methods> below +for details. + + +=head2 Methods + +=over 4 + +=item I<PACKAGE>->new(I<ARRAYREF [>, I<ARRAYREF]>) + +Returns a newly created C<Data::Dumper> object. The first argument is an +anonymous array of values to be dumped. The optional second argument is an +anonymous array of names for the values. The names need not have a leading +C<$> sign, and must be comprised of alphanumeric characters. You can begin +a name with a C<*> to specify that the dereferenced type must be dumped +instead of the reference itself, for ARRAY and HASH references. + +The prefix specified by C<$Data::Dumper::Varname> will be used with a +numeric suffix if the name for a value is undefined. + +Data::Dumper will catalog all references encountered while dumping the +values. Cross-references (in the form of names of substructures in perl +syntax) will be inserted at all possible points, preserving any structural +interdependencies in the original set of values. Structure traversal is +depth-first, and proceeds in order from the first supplied value to +the last. + +=item I<$OBJ>->Dump I<or> I<PACKAGE>->Dump(I<ARRAYREF [>, I<ARRAYREF]>) + +Returns the stringified form of the values stored in the object (preserving +the order in which they were supplied to C<new>), subject to the +configuration options below. In a list context, it returns a list +of strings corresponding to the supplied values. + +The second form, for convenience, simply calls the C<new> method on its +arguments before dumping the object immediately. + +=item I<$OBJ>->Seen(I<[HASHREF]>) + +Queries or adds to the internal table of already encountered references. +You must use C<Reset> to explicitly clear the table if needed. Such +references are not dumped; instead, their names are inserted wherever they +are encountered subsequently. This is useful especially for properly +dumping subroutine references. + +Expects an anonymous hash of name => value pairs. Same rules apply for names +as in C<new>. If no argument is supplied, will return the "seen" list of +name => value pairs, in a list context. Otherwise, returns the object +itself. + +=item I<$OBJ>->Values(I<[ARRAYREF]>) + +Queries or replaces the internal array of values that will be dumped. +When called without arguments, returns the values. Otherwise, returns the +object itself. + +=item I<$OBJ>->Names(I<[ARRAYREF]>) + +Queries or replaces the internal array of user supplied names for the values +that will be dumped. When called without arguments, returns the names. +Otherwise, returns the object itself. + +=item I<$OBJ>->Reset + +Clears the internal table of "seen" references and returns the object +itself. + +=back + +=head2 Functions + +=over 4 + +=item Dumper(I<LIST>) + +Returns the stringified form of the values in the list, subject to the +configuration options below. The values will be named C<$VAR>I<n> in the +output, where I<n> is a numeric suffix. Will return a list of strings +in a list context. + +=back + +=head2 Configuration Variables or Methods + +Several configuration variables can be used to control the kind of output +generated when using the procedural interface. These variables are usually +C<local>ized in a block so that other parts of the code are not affected by +the change. + +These variables determine the default state of the object created by calling +the C<new> method, but cannot be used to alter the state of the object +thereafter. The equivalent method names should be used instead to query +or set the internal state of the object. + +The method forms return the object itself when called with arguments, +so that they can be chained together nicely. + +=over 4 + +=item * + +$Data::Dumper::Indent I<or> I<$OBJ>->Indent(I<[NEWVAL]>) + +Controls the style of indentation. It can be set to 0, 1, 2 or 3. Style 0 +spews output without any newlines, indentation, or spaces between list +items. It is the most compact format possible that can still be called +valid perl. Style 1 outputs a readable form with newlines but no fancy +indentation (each level in the structure is simply indented by a fixed +amount of whitespace). Style 2 (the default) outputs a very readable form +which takes into account the length of hash keys (so the hash value lines +up). Style 3 is like style 2, but also annotates the elements of arrays +with their index (but the comment is on its own line, so array output +consumes twice the number of lines). Style 2 is the default. + +=item * + +$Data::Dumper::Purity I<or> I<$OBJ>->Purity(I<[NEWVAL]>) + +Controls the degree to which the output can be C<eval>ed to recreate the +supplied reference structures. Setting it to 1 will output additional perl +statements that will correctly recreate nested references. The default is +0. + +=item * + +$Data::Dumper::Pad I<or> I<$OBJ>->Pad(I<[NEWVAL]>) + +Specifies the string that will be prefixed to every line of the output. +Empty string by default. + +=item * + +$Data::Dumper::Varname I<or> I<$OBJ>->Varname(I<[NEWVAL]>) + +Contains the prefix to use for tagging variable names in the output. The +default is "VAR". + +=item * + +$Data::Dumper::Useqq I<or> I<$OBJ>->Useqq(I<[NEWVAL]>) + +When set, enables the use of double quotes for representing string values. +Whitespace other than space will be represented as C<[\n\t\r]>, "unsafe" +characters will be backslashed, and unprintable characters will be output as +quoted octal integers. Since setting this variable imposes a performance +penalty, the default is 0. C<Dump()> will run slower if this flag is set, +since the fast XSUB implementation doesn't support it yet. + +=item * + +$Data::Dumper::Terse I<or> I<$OBJ>->Terse(I<[NEWVAL]>) + +When set, Data::Dumper will emit single, non-self-referential values as +atoms/terms rather than statements. This means that the C<$VAR>I<n> names +will be avoided where possible, but be advised that such output may not +always be parseable by C<eval>. + +=item * + +$Data::Dumper::Freezer I<or> $I<OBJ>->Freezer(I<[NEWVAL]>) + +Can be set to a method name, or to an empty string to disable the feature. +Data::Dumper will invoke that method via the object before attempting to +stringify it. This method can alter the contents of the object (if, for +instance, it contains data allocated from C), and even rebless it in a +different package. The client is responsible for making sure the specified +method can be called via the object, and that the object ends up containing +only perl data types after the method has been called. Defaults to an empty +string. + +If an object does not support the method specified (determined using +UNIVERSAL::can()) then the call will be skipped. If the method dies a +warning will be generated. + +=item * + +$Data::Dumper::Toaster I<or> $I<OBJ>->Toaster(I<[NEWVAL]>) + +Can be set to a method name, or to an empty string to disable the feature. +Data::Dumper will emit a method call for any objects that are to be dumped +using the syntax C<bless(DATA, CLASS)-E<gt>METHOD()>. Note that this means that +the method specified will have to perform any modifications required on the +object (like creating new state within it, and/or reblessing it in a +different package) and then return it. The client is responsible for making +sure the method can be called via the object, and that it returns a valid +object. Defaults to an empty string. + +=item * + +$Data::Dumper::Deepcopy I<or> $I<OBJ>->Deepcopy(I<[NEWVAL]>) + +Can be set to a boolean value to enable deep copies of structures. +Cross-referencing will then only be done when absolutely essential +(i.e., to break reference cycles). Default is 0. + +=item * + +$Data::Dumper::Quotekeys I<or> $I<OBJ>->Quotekeys(I<[NEWVAL]>) + +Can be set to a boolean value to control whether hash keys are quoted. +A false value will avoid quoting hash keys when it looks like a simple +string. Default is 1, which will always enclose hash keys in quotes. + +=item * + +$Data::Dumper::Bless I<or> $I<OBJ>->Bless(I<[NEWVAL]>) + +Can be set to a string that specifies an alternative to the C<bless> +builtin operator used to create objects. A function with the specified +name should exist, and should accept the same arguments as the builtin. +Default is C<bless>. + +=item * + +$Data::Dumper::Pair I<or> $I<OBJ>->Pair(I<[NEWVAL]>) + +Can be set to a string that specifies the separator between hash keys +and values. To dump nested hash, array and scalar values to JavaScript, +use: C<$Data::Dumper::Pair = ' : ';>. Implementing C<bless> in JavaScript +is left as an exercise for the reader. +A function with the specified name exists, and accepts the same arguments +as the builtin. + +Default is: C< =E<gt> >. + +=item * + +$Data::Dumper::Maxdepth I<or> $I<OBJ>->Maxdepth(I<[NEWVAL]>) + +Can be set to a positive integer that specifies the depth beyond which +we don't venture into a structure. Has no effect when +C<Data::Dumper::Purity> is set. (Useful in debugger when we often don't +want to see more than enough). Default is 0, which means there is +no maximum depth. + +=item * + +$Data::Dumper::Useperl I<or> $I<OBJ>->Useperl(I<[NEWVAL]>) + +Can be set to a boolean value which controls whether the pure Perl +implementation of C<Data::Dumper> is used. The C<Data::Dumper> module is +a dual implementation, with almost all functionality written in both +pure Perl and also in XS ('C'). Since the XS version is much faster, it +will always be used if possible. This option lets you override the +default behavior, usually for testing purposes only. Default is 0, which +means the XS implementation will be used if possible. + +=item * + +$Data::Dumper::Sortkeys I<or> $I<OBJ>->Sortkeys(I<[NEWVAL]>) + +Can be set to a boolean value to control whether hash keys are dumped in +sorted order. A true value will cause the keys of all hashes to be +dumped in Perl's default sort order. Can also be set to a subroutine +reference which will be called for each hash that is dumped. In this +case C<Data::Dumper> will call the subroutine once for each hash, +passing it the reference of the hash. The purpose of the subroutine is +to return a reference to an array of the keys that will be dumped, in +the order that they should be dumped. Using this feature, you can +control both the order of the keys, and which keys are actually used. In +other words, this subroutine acts as a filter by which you can exclude +certain keys from being dumped. Default is 0, which means that hash keys +are not sorted. + +=item * + +$Data::Dumper::Deparse I<or> $I<OBJ>->Deparse(I<[NEWVAL]>) + +Can be set to a boolean value to control whether code references are +turned into perl source code. If set to a true value, C<B::Deparse> +will be used to get the source of the code reference. Using this option +will force using the Perl implementation of the dumper, since the fast +XSUB implementation doesn't support it. + +Caution : use this option only if you know that your coderefs will be +properly reconstructed by C<B::Deparse>. + +=back + +=head2 Exports + +=over 4 + +=item Dumper + +=back + +=head1 EXAMPLES + +Run these code snippets to get a quick feel for the behavior of this +module. When you are through with these examples, you may want to +add or change the various configuration variables described above, +to see their behavior. (See the testsuite in the Data::Dumper +distribution for more examples.) + + + use Data::Dumper; + + package Foo; + sub new {bless {'a' => 1, 'b' => sub { return "foo" }}, $_[0]}; + + package Fuz; # a weird REF-REF-SCALAR object + sub new {bless \($_ = \ 'fu\'z'), $_[0]}; + + package main; + $foo = Foo->new; + $fuz = Fuz->new; + $boo = [ 1, [], "abcd", \*foo, + {1 => 'a', 023 => 'b', 0x45 => 'c'}, + \\"p\q\'r", $foo, $fuz]; + + ######## + # simple usage + ######## + + $bar = eval(Dumper($boo)); + print($@) if $@; + print Dumper($boo), Dumper($bar); # pretty print (no array indices) + + $Data::Dumper::Terse = 1; # don't output names where feasible + $Data::Dumper::Indent = 0; # turn off all pretty print + print Dumper($boo), "\n"; + + $Data::Dumper::Indent = 1; # mild pretty print + print Dumper($boo); + + $Data::Dumper::Indent = 3; # pretty print with array indices + print Dumper($boo); + + $Data::Dumper::Useqq = 1; # print strings in double quotes + print Dumper($boo); + + $Data::Dumper::Pair = " : "; # specify hash key/value separator + print Dumper($boo); + + + ######## + # recursive structures + ######## + + @c = ('c'); + $c = \@c; + $b = {}; + $a = [1, $b, $c]; + $b->{a} = $a; + $b->{b} = $a->[1]; + $b->{c} = $a->[2]; + print Data::Dumper->Dump([$a,$b,$c], [qw(a b c)]); + + + $Data::Dumper::Purity = 1; # fill in the holes for eval + print Data::Dumper->Dump([$a, $b], [qw(*a b)]); # print as @a + print Data::Dumper->Dump([$b, $a], [qw(*b a)]); # print as %b + + + $Data::Dumper::Deepcopy = 1; # avoid cross-refs + print Data::Dumper->Dump([$b, $a], [qw(*b a)]); + + + $Data::Dumper::Purity = 0; # avoid cross-refs + print Data::Dumper->Dump([$b, $a], [qw(*b a)]); + + ######## + # deep structures + ######## + + $a = "pearl"; + $b = [ $a ]; + $c = { 'b' => $b }; + $d = [ $c ]; + $e = { 'd' => $d }; + $f = { 'e' => $e }; + print Data::Dumper->Dump([$f], [qw(f)]); + + $Data::Dumper::Maxdepth = 3; # no deeper than 3 refs down + print Data::Dumper->Dump([$f], [qw(f)]); + + + ######## + # object-oriented usage + ######## + + $d = Data::Dumper->new([$a,$b], [qw(a b)]); + $d->Seen({'*c' => $c}); # stash a ref without printing it + $d->Indent(3); + print $d->Dump; + $d->Reset->Purity(0); # empty the seen cache + print join "----\n", $d->Dump; + + + ######## + # persistence + ######## + + package Foo; + sub new { bless { state => 'awake' }, shift } + sub Freeze { + my $s = shift; + print STDERR "preparing to sleep\n"; + $s->{state} = 'asleep'; + return bless $s, 'Foo::ZZZ'; + } + + package Foo::ZZZ; + sub Thaw { + my $s = shift; + print STDERR "waking up\n"; + $s->{state} = 'awake'; + return bless $s, 'Foo'; + } + + package Foo; + use Data::Dumper; + $a = Foo->new; + $b = Data::Dumper->new([$a], ['c']); + $b->Freezer('Freeze'); + $b->Toaster('Thaw'); + $c = $b->Dump; + print $c; + $d = eval $c; + print Data::Dumper->Dump([$d], ['d']); + + + ######## + # symbol substitution (useful for recreating CODE refs) + ######## + + sub foo { print "foo speaking\n" } + *other = \&foo; + $bar = [ \&other ]; + $d = Data::Dumper->new([\&other,$bar],['*other','bar']); + $d->Seen({ '*foo' => \&foo }); + print $d->Dump; + + + ######## + # sorting and filtering hash keys + ######## + + $Data::Dumper::Sortkeys = \&my_filter; + my $foo = { map { (ord, "$_$_$_") } 'I'..'Q' }; + my $bar = { %$foo }; + my $baz = { reverse %$foo }; + print Dumper [ $foo, $bar, $baz ]; + + sub my_filter { + my ($hash) = @_; + # return an array ref containing the hash keys to dump + # in the order that you want them to be dumped + return [ + # Sort the keys of %$foo in reverse numeric order + $hash eq $foo ? (sort {$b <=> $a} keys %$hash) : + # Only dump the odd number keys of %$bar + $hash eq $bar ? (grep {$_ % 2} keys %$hash) : + # Sort keys in default order for all other hashes + (sort keys %$hash) + ]; + } + +=head1 BUGS + +Due to limitations of Perl subroutine call semantics, you cannot pass an +array or hash. Prepend it with a C<\> to pass its reference instead. This +will be remedied in time, now that Perl has subroutine prototypes. +For now, you need to use the extended usage form, and prepend the +name with a C<*> to output it as a hash or array. + +C<Data::Dumper> cheats with CODE references. If a code reference is +encountered in the structure being processed (and if you haven't set +the C<Deparse> flag), an anonymous subroutine that +contains the string '"DUMMY"' will be inserted in its place, and a warning +will be printed if C<Purity> is set. You can C<eval> the result, but bear +in mind that the anonymous sub that gets created is just a placeholder. +Someday, perl will have a switch to cache-on-demand the string +representation of a compiled piece of code, I hope. If you have prior +knowledge of all the code refs that your data structures are likely +to have, you can use the C<Seen> method to pre-seed the internal reference +table and make the dumped output point to them, instead. See L</EXAMPLES> +above. + +The C<Useqq> and C<Deparse> flags makes Dump() run slower, since the +XSUB implementation does not support them. + +SCALAR objects have the weirdest looking C<bless> workaround. + +Pure Perl version of C<Data::Dumper> escapes UTF-8 strings correctly +only in Perl 5.8.0 and later. + +=head2 NOTE + +Starting from Perl 5.8.1 different runs of Perl will have different +ordering of hash keys. The change was done for greater security, +see L<perlsec/"Algorithmic Complexity Attacks">. This means that +different runs of Perl will have different Data::Dumper outputs if +the data contains hashes. If you need to have identical Data::Dumper +outputs from different runs of Perl, use the environment variable +PERL_HASH_SEED, see L<perlrun/PERL_HASH_SEED>. Using this restores +the old (platform-specific) ordering: an even prettier solution might +be to use the C<Sortkeys> filter of Data::Dumper. + +=head1 AUTHOR + +Gurusamy Sarathy gsar@activestate.com + +Copyright (c) 1996-98 Gurusamy Sarathy. All rights reserved. +This program is free software; you can redistribute it and/or +modify it under the same terms as Perl itself. + +=head1 VERSION + +Version 2.125 (Aug 8 2009) + +=head1 SEE ALSO + +perl(1) + +=cut |