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DumpingPerl 6
AmsterdamX.pm, 8 Jun 2017
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Per
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Per
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Plainmy $rx = rx/ <[ a .. z ]> <[ 1 .. 9 ]> /;my $string = ':::abc123::';my $match = $string ~~ $rx;
put $match;
c1
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Per
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.gistmy $rx = rx/ <[ a .. z ]> <[ 1 .. 9 ]> /;my $string = ':::abc123::';my $match = $string ~~ $rx;
say $match; # put $match.gist
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Per
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.perlmy $rx = rx/ <[ a .. z ]> <[ 1 .. 9 ]> /;my $string = ':::abc123::';my $match = $string ~~ $rx;
put $match.perl;
Match.new(list => (), made => Any, pos => 7, hash => Map.new(()), orig => ":::abc123::", from => 5)
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Per
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Pretty::Printeruse Pretty::Printer; # From Jeff Goff
my $rx = rx/ <[ a .. z ]> <[ 1 .. 9 ]> /;my $string = ':::abc123::';my $match = $string ~~ $rx;
Pretty::Printer.new.pp: $match;
Any
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Per
l 6
method _pp($ds,$depth){my Str $str;given $ds.WHAT
{when Hash { $str ~= self.Hash($ds,$depth) }when Array { $str ~= self.Array($ds,$depth) }when Pair { $str ~= self.Pair($ds,$depth) }when Str { $str ~= $ds.perl }when Numeric { $str ~= ~$ds }when Nil { $str ~= q{Nil} }when Any { $str ~= q{Any} }}
return self.indent-string($str,$depth);}
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Per
l 6
PrettyDumpuse PrettyDump;
my $rx = rx/ <[ a .. z ]> <[ 1 .. 9 ]> /;my $string = ':::abc123::';my $match = $string ~~ $rx;
put PrettyDump.new.dump: $match;
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Per
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Match.new(:from(5),:hash(Map.new()),:list($()),:made(Mu),:orig(":::abc123::"),:pos(7),:to(7)
)
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Per
l 6
By Type
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Per
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method _pp($ds,$depth){my Str $str;given $ds.WHAT
{# Check more derived types first.when Match { $str ~= self.Match($ds,$depth) }when Hash { $str ~= self.Hash($ds,$depth) }when Array { $str ~= self.Array($ds,$depth) }when Map { $str ~= self.Map($ds,$depth) }when List { $str ~= self.List($ds,$depth) }when Pair { $str ~= self.Pair($ds,$depth) }when Str { $str ~= $ds.perl }when Numeric { $str ~= ~$ds }when Nil { $str ~= q{Nil} }when Any { $str ~= q{Any} }}
return self.indent-string($str,$depth);}
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Per
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Per Class
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Per
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class SomeClass { … method PrettyDump ( $pretty, $ds, $depth ) { … } }
my $pretty = PrettyDump.new;
my $some-object = SomeClass.new;
put $pretty.dump: $some-object;
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Per
l 6
use PrettyDump;
my $pretty = PrettyDump.new;
my Int $a = 137;put $pretty.dump: $a;
my $b = $a but role {method PrettyDump ( $pretty, $depth = 0 ) {
"({self.^name}) {self}";}
};put $pretty.dump: $b;
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Per
l 6
method dump ( $ds, $depth = 0 ) {put "In dump. Got ", $ds.^name;my Str $str;
if $ds.can: 'PrettyDump' {$str ~= $ds.PrettyDump: self;}
elsif $ds ~~ Numeric {$str ~= self.Numeric: $ds, $depth;}
elsif self.can: $ds.^name {my $what = $ds.^name;$str ~= self."$what"( $ds, $depth );}
else {die "Could not handle " ~ $ds.perl;}
return self.indent-string: $str, $depth;}
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Per
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Per Object
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Per
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Decorate the Dumper
my $pretty = PrettyDump.new;
class SomeClass { … }
my $handler = sub ( $pretty, $ds, Int $depth = 0 ) {...}
$pretty.add-handler: 'SomeClass', $handler;
put $pretty.dump: $SomeClass-object;
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Per
l 6
method dump ( $ds, Int $depth = 0 --> Str ) {my Str $str = do {
# If the PrettyDump object has a user-defined handler# for this type, prefer that oneif self.handles: $ds.^name {
self!handle: $ds, $depth;}
# The object might have its own method to dump # its structureelsif $ds.can: 'PrettyDump' {
$ds.PrettyDump: self;}
# If it's any sort of Numeric, we'll handle it # and dispatch furtherelsif $ds ~~ Numeric {
self!Numeric: $ds, $depth;}
…
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Per
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# If we have a method name that matches the class, we'll# use that.elsif self.can: $ds.^name {
my $what = $ds.^name;self."$what"( $ds, $depth );}
# If the class inherits from something that we know# about, use the most specific one that we know aboutelsif $ds.^parents.grep(
{ self.can: $_.^name } ).elems > 0 {my Str $str = '';for $ds.^parents -> $type {
my $what = $type.^name;next unless self.can( $what );$str ~= self."$what"(
$ds, $depth, "{$ds.^name}.new(", ')' );last;}
$str;}
…
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Per
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# If we're this far and the object has a .Str method,# we'll use that:elsif $ds.can: 'Str' {
"({$ds.^name}): " ~ $ds.Str;}
# Finally, we'll put a placeholder method thereelse {
"(Unhandled {$ds.^name})"}
};
return self!indent-string: $str, $depth;}
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Per
l 6
Not Data::Dumper• Does not produce eval-able code• Does not know what it has already seen• Missing a few formatting features
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Per
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What else might it do?• Handle more data types• More configurable formatting options• Formatting hooks• Send email
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Per
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Questions
