Rules / Types, classes & roles / composite

Blob Reference

Immutable buffer for binary data ('Binary Large OBject')

What it is #

enum as the B<second> parameter to these methods.  If no endianness is

Routines #

Signatures are reproduced from the documentation, including their declared return types. A routine listed here is part of the type's published interface; whether Raku++ implements it is a separate question, answered by the examples below.

method new #

multi method new(Blob:)
multi method new(Blob: Blob:D $blob)
multi method new(Blob: int @values)
multi method new(Blob: @values)
multi method new(Blob: *@values)

Creates an empty Blob, or a new Blob from another Blob, or from a list of integers or values (which will have to be coerced into integers):

method Bool #

multi method Bool(Blob:D:)

Returns False if and only if the buffer is empty.

method Capture #

method Capture(Blob:D:)

Converts the object to a List which is, in turn, coerced to a Capture.

method elems #

multi method elems(Blob:D:)

Returns the number of elements of the buffer.

method bytes #

method bytes(Blob:D: --> Int:D)

Returns Int:D.

Returns the number of bytes used by the elements in the buffer.

method chars #

method chars(Blob:D:)

Throws X::Buf::AsStr with chars as payload.

method Str #

multi method Str(Blob:D:)

Throws X::Buf::AsStr with Str as payload. In order to convert to a Str you need to use .decode.

method Stringy #

multi method Stringy(Blob:D:)

Throws X::Buf::AsStr with Stringy as payload.

method decode #

multi method decode(Blob:D: $encoding = self.encoding // "utf-8")

Applies an encoding to turn the blob into a Str; the encoding will be UTF-8 by default. On malformed utf-8 .decode will throw X::AdHoc. To handle sloppy utf-8 use utf8-c8.

method list #

multi method list(Blob:D:)

Returns a List of integers:

method gist #

method gist(Blob:D: --> Str:D)

Returns Str:D.

Returns the string containing the "gist" of the Blob, listing up to the first 100 elements, separated by space, appending an ellipsis if the Blob has more than 100 elements.

method subbuf #

multi method subbuf(Int $from, Int $len = self.elems --> Blob:D)
multi method subbuf(Range $range --> Blob:D)
multi method subbuf(Blob:D: &From)
multi method subbuf(Blob:D: Int:D $From, &End)
multi method subbuf(Blob:D: &From, &End)
multi method subbuf(Blob:D: \from, Whatever)
multi method subbuf(Blob:D: \from, Numeric \length)

Returns Blob:D.

Extracts a part of the invocant buffer, starting from the index with elements $from, and taking $len elements (or less if the buffer is shorter), and creates a new buffer as the result. For convenience, also allows a Range to be specified to indicate which part of the invocant buffer you would like:

method allocate #

multi method allocate(Blob:U: Int:D $elements)
multi method allocate(Blob:U: Int:D $elements, int $value)
multi method allocate(Blob:U: Int:D $elements, Int:D \value)
multi method allocate(Blob:U: Int:D $elements, Mu:D $got)
multi method allocate(Blob:U: Int:D $elements, int @values)
multi method allocate(Blob:U: Int:D $elements, Blob:D $blob)
multi method allocate(Blob:U: Int:D $elements, @values)

Returns a newly created Blob object with the given number of elements. Optionally takes a second argument that indicates the pattern with which to fill the Blob: this can be a single (possibly native) integer value, or any Iterable that generates integer values, including another Blob. The pattern will be repeated if not enough values are given to fill the entire Blob.

routine unpack #

multi method unpack(Blob:D: Str:D $template)
multi method unpack(Blob:D: @template)
multi        unpack(Blob:D \blob, Str:D $template)
multi        unpack(Blob:D \blob, @template)

This method is considered experimental, in order to use it you will need to do: Extracts features from the blob according to the template string, and returns them as a list. The template string consists of zero or more units that begin with an ASCII letter, and are optionally followed by a quantifier. The quantifier can be * (which typically stands for "use up the rest of the Blob here"), or a

sub pack #

multi pack(Str $template, *@items)
multi pack(@template, *@items)

This subroutine is considered experimental, in order to use it you will need to do: Packs the given items according to the template and returns a buffer containing the packed bytes. The template string consists of zero or more units that begin with an ASCII letter, and are optionally followed by a quantifier. For details, see unpack.

method reverse #

method reverse(Blob:D: --> Blob:D)

Returns Blob:D.

Returns a Blob with all elements in reversed order. These methods are available on the blob8 (and buf8) types only. They allow low level access to reading bytes from the underlying data and interpreting them in different ways with regards to type (integer or floating point (num)), size (8, 16, 32, 64 or 128 bits), signed or unsigned (for integer values) and endianness (native, little and big endianness). The returned values are

method read-uint8 #

method read-uint8(blob8:D: uint $pos, $endian = NativeEndian --> uint)

Returns uint.

Returns an unsigned native integer value for the byte at the given position. The $endian parameter has no meaning, but is available for consistency.

method read-int8 #

method read-int8(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native int value for the byte at the given position. The $endian parameter has no meaning, but is available for consistency.

method read-uint16 #

method read-uint16(blob8:D: uint $pos, $endian = NativeEndian --> uint)

Returns uint.

Returns a native uint value for the two bytes starting at the given position.

method read-int16 #

method read-int16(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native int value for the two bytes starting at the given position.

method read-uint32 #

method read-uint32(blob8:D: uint $pos, $endian = NativeEndian --> uint)

Returns uint.

Returns a native uint value for the four bytes starting at the given position.

method read-int32 #

method read-int32(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native int value for the four bytes starting at the given position.

method read-uint64 #

method read-uint64(blob8:D: uint $pos, $endian = NativeEndian --> UInt:D)

Returns UInt:D.

Returns an unsigned integer value for the eight bytes starting at the given position.

method read-int64 #

method read-int64(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native int value for the eight bytes starting at the given position.

method read-uint128 #

method read-uint128(blob8:D: uint $pos, $endian = NativeEndian --> UInt:D)

Returns UInt:D.

Returns an unsigned integer value for the sixteen bytes starting at the given position.

method read-int128 #

method read-int128(blob8:D: uint $pos, $endian = NativeEndian --> Int:D)

Returns Int:D.

Returns an integer value for the sixteen bytes starting at the given position.

method read-num32 #

method read-num32(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native num value for the four bytes starting at the given position.

method read-num64 #

method read-num64(blob8:D: uint $pos, $endian = NativeEndian --> int)

Returns int.

Returns a native num value for the eight bytes starting at the given position.

method read-ubits #

method read-ubits(blob8:D: uint $pos, uint $bits --> UInt:D)

Returns UInt:D.

Returns an unsigned integer value for the bits from the given bit offset and given number of bits. The endianness of the bits is assumed to be BigEndian.

method read-bits #

method read-bits(blob8:D: uint $pos, uint $bits --> Int:D)

Returns Int:D.

Returns a signed integer value for the bits from the given bit offset and given number of bits. The endianness of the bits is assumed to be BigEndian.

method Buf #

method Buf(Blob:D: --> Buf:D)

Returns Buf:D.

Available as of the 2021.06 Rakudo compiler release. Coerces the invocant into a mutable Buf object.

Examples, run three ways #

Every example below comes from the official documentation, together with the output that documentation asserts. Each was then executed by Rakudo and by Raku++ when this page was built. Where the three agree, one result is shown; where they do not, all three are — because which of them is wrong is exactly the information worth having.

3 all-differ · 1 doc-drift · 6 no-output · 9 ok · 1 rakupp-differs

role Blob[::T = uint8] does Positional[T] does Stringy { }

Not executed: the documentation states no expected output for this example.

my $b = Blob[int32].new(3, -3, 0xff32, -44);
say $b; # OUTPUT: «Blob[int32]:0x<03 -3 FF32 -2C>␤»
Documentation
Blob[int32]:0x<03 -3 FF32 -2C>
Rakudo
Blob[int32]:0x<00000003 FFFFFFFD 0000FF32 FFFFFFD4>
Raku++
Blob[uint32]:0x<00000003 FFFFFFFD 0000FF32 FFFFFFD4>

All three differ. Needs a human.

Not yet examined. Which of these is correct has not been established — do not treat either engine as settled here.

my $blob = blob8.new(3, 6, 254);
say $blob; # OUTPUT: «Blob[uint8]:0x<03 06 FE>␤»
Output
Blob[uint8]:0x<03 06 FE>

Documentation, Rakudo and Raku++ all agree.

my $blob = Blob.new([1, 2, 3]);
say Blob.new(<1 2 3>); # OUTPUT: «Blob:0x<01 02 03>␤»
Output
Blob:0x<01 02 03>

Documentation, Rakudo and Raku++ all agree.

my $blob = Blob.new();
say $blob.Bool; # OUTPUT: «False␤»
$blob = Blob.new([1, 2, 3]);
say $blob.Bool; # OUTPUT: «True␤»
Output
False
True

Documentation, Rakudo and Raku++ all agree.

my $blob = Blob.new([1, 2, 3]);
say $blob.elems; # OUTPUT: «3␤»
Output
3

Documentation, Rakudo and Raku++ all agree.

say Blob.new([1, 2, 3]).bytes;      # OUTPUT: «3␤»
say blob16.new([1, 2, 3]).bytes;    # OUTPUT: «6␤»
say blob64.new([1, 2, 3]).bytes;    # OUTPUT: «24␤»
Output
3
6
24

Documentation, Rakudo and Raku++ all agree.

multi method decode(Blob:D: $encoding, Str :$replacement!,
                Bool:D :$strict = False)

Not executed: the documentation states no expected output for this example.

multi method decode(Blob:D: $encoding, Bool:D :$strict = False)

Not executed: the documentation states no expected output for this example.

my Blob $blob = "string".encode('utf-8');
say $blob.decode('utf-8'); # OUTPUT: «string␤»
Output
string

Documentation, Rakudo and Raku++ all agree.

say "zipi".encode("ascii").list; # OUTPUT: «(122 105 112 105)␤»
Output
(122 105 112 105)

Documentation, Rakudo and Raku++ all agree.

put Blob.new(1, 2, 3).gist; # OUTPUT: «Blob:0x<01 02 03>␤»
put Blob.new(1..2000).gist;
# OUTPUT:
# Blob:0x<01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15
# 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27 28 29 2A 2B 2C
# 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43
# 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A
# 5B 5C 5D 5E 5F 60 61 62 63 64 ...>
Documentation
Blob:0x<01 02 03>
Rakudo
Blob:0x<01 02 03>
Blob:0x<01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 ...>
Raku++
Blob:0x<01 02 03>
Blob:0x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

All three differ. Needs a human.

Not yet examined. Which of these is correct has not been established — do not treat either engine as settled here.

say Blob.new(1..10).subbuf(2, 4);    # OUTPUT: «Blob:0x<03 04 05 06>␤»
say Blob.new(1..10).subbuf(*-2);     # OUTPUT: «Blob:0x<09 0a>␤»
say Blob.new(1..10).subbuf(*-5,2);   # OUTPUT: «Blob:0x<06 07>␤»
Documentation
Blob:0x<03 04 05 06>
Blob:0x<09 0a>
Blob:0x<06 07>
Rakudo
Blob:0x<03 04 05 06>
Blob:0x<09 0A>
Blob:0x<06 07>
Raku++
Blob:0x<03 04 05 06>
Blob:0x<09 0A>
Blob:0x<06 07>

Both engines agree; the documentation states something else. Trust the engines.

say Blob.new(1..10).subbuf(2..5);    # OUTPUT: «Blob:0x<03 04 05 06>␤»
Output
Blob:0x<03 04 05 06>

Documentation, Rakudo and Raku++ all agree.

my Blob $b0 = Blob.allocate(10,0);
$b0.say; # OUTPUT: «Blob:0x<00 00 00 00 00 00 00 00 00 00>␤»
Output
Blob:0x<00 00 00 00 00 00 00 00 00 00>

Documentation, Rakudo and Raku++ all agree.

use experimental :pack;

Not executed: the documentation states no expected output for this example.

Letter  Meaning
======  =======
A       Extract a string, where each element of the Blob maps to a codepoint
a       Same as 'A'
C       Extract an element from the blob as an integer
H       Extracts a hex string
L       Extracts four elements and returns them as a single unsigned integer
n       Extracts two elements and combines them in "network" (BigEndian) byte order into a single integer
N       Extracts four elements and combines them in "network" (BigEndian) byte order into a single integer
S       Extracts two elements and returns them as a single unsigned integer
v       Same as 'S'
V       Same as 'L'
x       Drop an element from the blob (that is, ignore it)
Z       Same as 'A'

Not executed: the documentation states no expected output for this example.

use experimental :pack;
say Blob.new(1..10).unpack("C*");
# OUTPUT: «(1 2 3 4 5 6 7 8 9 10)␤»
Documentation
(1 2 3 4 5 6 7 8 9 10)
Rakudo
(1 2 3 4 5 6 7 8 9 10)
Raku++

Raku++ disagrees with both the documentation and Rakudo — a defect.

use experimental :pack;

Not executed: the documentation states no expected output for this example.

say Blob.new([1, 2, 3]).reverse;    # OUTPUT: «Blob:0x<03 02 01>␤»
say blob16.new([2]).reverse;        # OUTPUT: «Blob[uint16]:0x<02>␤»
say blob32.new([16, 32]).reverse;   # OUTPUT: «Blob[uint32]:0x<20 10>␤»
Documentation
Blob:0x<03 02 01>
Blob[uint16]:0x<02>
Blob[uint32]:0x<20 10>
Rakudo
Blob:0x<03 02 01>
Blob[uint16]:0x<0002>
Blob[uint32]:0x<00000020 00000010>
Raku++
(3 2 1)
(2)
(32 16)

All three differ. Needs a human.

Not yet examined. Which of these is correct has not been established — do not treat either engine as settled here.