thedesk/app/node_modules/buffers/README.markdown
2018-02-18 16:29:06 +09:00

2.7 KiB

buffers

Treat a collection of Buffers as a single contiguous partially mutable Buffer.

Where possible, operations execute without creating a new Buffer and copying
everything over.

This is a cleaner more Buffery rehash of
bufferlist.

example

slice

var Buffers = require('buffers');
var bufs = Buffers();
bufs.push(new Buffer([1,2,3]));
bufs.push(new Buffer([4,5,6,7]));
bufs.push(new Buffer([8,9,10]));

console.dir(bufs.slice(2,8))

output:

$ node examples/slice.js 
<Buffer 03 04 05 06 07 08>

splice

var Buffers = require('buffers');
var bufs = Buffers([
    new Buffer([1,2,3]),
    new Buffer([4,5,6,7]),
    new Buffer([8,9,10]),
]);

var removed = bufs.splice(2, 4);
console.dir({
    removed : removed.slice(),
    bufs : bufs.slice(),
});

output:

$ node examples/splice.js
{ removed: <Buffer 03 04 05 06>,
  bufs: <Buffer 01 02 07 08 09 0a> }

methods

Buffers(buffers)

Create a Buffers with an array of Buffers if specified, else [].

.push(buf1, buf2...)

Push buffers onto the end. Just like Array.prototype.push.

.unshift(buf1, buf2...)

Unshift buffers onto the head. Just like Array.prototype.unshift.

.slice(i, j)

Slice a range out of the buffer collection as if it were contiguous.
Works just like the Array.prototype.slice version.

.splice(i, howMany, replacements)

Splice the buffer collection as if it were contiguous.
Works just like Array.prototype.splice, even the replacement part!

.copy(dst, dstStart, start, end)

Copy the buffer collection as if it were contiguous to the dst Buffer with the
specified bounds.
Works just like Buffer.prototype.copy.

.get(i)

Get a single element at index i.

.set(i, x)

Set a single element's value at index i.

.indexOf(needle, offset)

Find a string or buffer needle inside the buffer collection. Returns
the position of the search string or -1 if the search string was not
found.

Provide an offset to skip that number of characters at the beginning
of the search. This can be used to find additional matches.

This function will return the correct result even if the search string
is spread out over multiple internal buffers.

.toBuffer()

Convert the buffer collection to a single buffer, equivalent with .slice(0, buffers.length);

.toString(encoding, start, end)

Decodes and returns a string from the buffer collection.
Works just like Buffer.prototype.toString