Add a Blob class as a bridge between string, bytes and streams

[thekid]

This pull request adds an io.Blob class.

Examples

Creating a blob from various inputs:

use io\Blob;
use io\streams\{Streams, MemoryInputStream};
use util\Bytes;

$test= new Blob('Test');
$test= new Blob(new Bytes('Test'));
$test= new Blob(new MemoryInputStream('Test'));
$test= new Blob(['Te', 'st']);

$test->bytes();                    // util.Bytes("Test")
Streams::readAll($test->stream()); // "Test"
(string)$test;                     // "Test"

Iterating slices of a stream:

use io\Blob;
use io\streams\FileInputStream;

// Will echo the file's contents in slices of 8192 bytes
$blob= new Blob(new FileInputStream($argv[1]));
foreach ($blob->slices(size: 8192) as $slice) {
  echo $slice;
}

See also

• https://developer.mozilla.org/en-US/docs/Web/API/Blob
• https://jsdev.space/howto/blob-file-handling-guide/