Buffer

Utilities for working with buffers.

Buffers are data structures that automatically expand as more data is appended. They are useful for storing and operating on an unknown number of bytes. All set or append operations mutate the buffer.

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from "buffer" include Buffer

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Buffer.make(64)

Types

Type declarations included in the Buffer module.

Buffer.Buffer

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type Buffer

Values

Functions and constants included in the Buffer module.

Buffer.make

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make : (initialSize: Number) => Buffer

Creates a fresh buffer, initially empty.

The initialSize parameter is the initial size of the internal byte sequence that holds the buffer contents. That byte sequence is automatically reallocated when more than initialSize bytes are stored in the buffer, but shrinks back to initialSize characters when reset is called.

Parameters:

Returns:

Throws:

InvalidArgument(String)

• When the initialSize is a negative number

Examples:

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Buffer.make(0)

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Buffer.make(64)

Buffer.length

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length : (buffer: Buffer) => Number

Gets the number of bytes currently contained in a buffer.

Parameters:

Returns:

Examples:

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Buffer.length(Buffer.make(32)) == 0

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let buf = Buffer.make(32)
Buffer.addInt32(1l, buf)
assert Buffer.length(buf) == 4

Buffer.clear

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clear : (buffer: Buffer) => Void

Clears data in the buffer and sets its length to zero.

This operation does not resize the underlying byte sequence.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addInt32(1l, buf)
assert Buffer.length(buf) == 4
Buffer.clear(buf)
assert Buffer.length(buf) == 0

Buffer.reset

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reset : (buffer: Buffer) => Void

Empty a buffer and deallocate the internal byte sequence holding the buffer contents.

This operation resizes the underlying byte sequence to the initial size of the buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addInt32(1l, buf)
assert Buffer.length(buf) == 4
Buffer.reset(buf)
assert Buffer.length(buf) == 0

Buffer.truncate

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truncate : (length: Number, buffer: Buffer) => Void

Shortens a buffer to the given length.

This operation does not resize the underlying byte sequence.

Parameters:

Throws:

IndexOutOfBounds

• When the length is negative
• When the length is greater than the buffer size

Examples:

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let buf = Buffer.make(0)
Buffer.addInt32(1l, buf)
assert Buffer.length(buf) == 4
Buffer.truncate(1, buf)
assert Buffer.length(buf) == 1

Buffer.toBytes

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toBytes : (buffer: Buffer) => Bytes

Returns a copy of the current contents of the buffer as a byte sequence.

Parameters:

Returns:

Examples:

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let buf = Buffer.make(0)
Buffer.addString("test", buf)
assert Buffer.toBytes(buf) == b"test"

Buffer.toBytesSlice

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toBytesSlice : (start: Number, length: Number, buffer: Buffer) => Bytes

Returns a slice of the current contents of the buffer as a byte sequence.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When start is negative
• When start is greater than or equal to the buffer size
• When start + length is greater than the buffer size

Examples:

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let buf = Buffer.make(0)
Buffer.addString("HelloWorld", buf)
assert Buffer.toBytesSlice(0, 5, buf) == b"Hello"

Buffer.toString

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toString : (buffer: Buffer) => String

Returns a copy of the current contents of the buffer as a string.

Parameters:

Returns:

Examples:

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let buf = Buffer.make(0)
Buffer.addString("HelloWorld", buf)
assert Buffer.toString(buf) == "HelloWorld"

Buffer.toStringSlice

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toStringSlice : (start: Number, length: Number, buffer: Buffer) => String

Returns a copy of a subset of the current contents of the buffer as a string.

Parameters:

Returns:

Examples:

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let buf = Buffer.make(0)
Buffer.addString("HelloWorld", buf)
assert Buffer.toStringSlice(0, 5, buf) == "Hello"

Buffer.addBytes

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addBytes : (bytes: Bytes, buffer: Buffer) => Void

Appends a byte sequence to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addBytes(b"test", buf)
assert Buffer.toBytes(buf) == b"test"

Buffer.addString

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addString : (string: String, buffer: Buffer) => Void

Appends the bytes of a string to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addString("Hello", buf)
assert Buffer.toString(buf) == "Hello"

Buffer.addChar

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addChar : (char: Char, buffer: Buffer) => Void

Appends the bytes of a character to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addChar('H', buf)
assert Buffer.toString(buf) == "H"

Buffer.addCharFromCodePoint

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addCharFromCodePoint : (codePoint: Number, buffer: Buffer) => Void

Appends a character represented by a code point to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addCharFromCodePoint(72, buf)
assert Buffer.toString(buf) == "H"

Buffer.addStringSlice

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addStringSlice :
  (start: Number, end: Number, string: String, buffer: Buffer) => Void

Appends the bytes of a subset of a string to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addStringSlice(0, 5, "HelloWorld", buf)
assert Buffer.toString(buf) == "Hello"

Buffer.addBytesSlice

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addBytesSlice :
  (start: Number, length: Number, bytes: Bytes, buffer: Buffer) => Void

Appends the bytes of a subset of a byte sequence to a buffer.

Parameters:

Throws:

IndexOutOfBounds

• When the start is negative
• When the start is greater than or equal to the bytes size
• When the length is negative
• When the length is greater than the bytes length minus start

Examples:

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let buf = Buffer.make(0)
Buffer.addBytesSlice(0, 5, b"HelloWorld", buf)
assert Buffer.toString(buf) == "Hello"

Buffer.addBuffer

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addBuffer : (srcBuffer: Buffer, dstBuffer: Buffer) => Void

Appends the bytes of a source buffer to destination buffer.

The source buffer is not mutated by this operation. The destination buffer, however, is mutated.

Parameters:

Examples:

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let buf1 = Buffer.make(0)
Buffer.addString("Hello", buf1)
let buf2 = Buffer.make(0)
Buffer.addString("World", buf2)
Buffer.addBuffer(buf2, buf1)
assert Buffer.toString(buf1) == "HelloWorld"

Buffer.addBufferSlice

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addBufferSlice :
  (start: Number, length: Number, srcBuffer: Buffer, dstBuffer: Buffer) =>
   Void

Appends the bytes of a part of a buffer to the end of the buffer

The source buffer is not mutated by this operation. The destination buffer, however, is mutated.

Parameters:

Examples:

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let buf1 = Buffer.make(0)
Buffer.addString("Hello", buf1)
let buf2 = Buffer.make(0)
Buffer.addString("HiWorld", buf2)
Buffer.addBufferSlice(2, 5, buf2, buf1)
assert Buffer.toString(buf1) == "HelloWorld"

Buffer.getInt8

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getInt8 : (index: Number, buffer: Buffer) => Int8

Gets a signed 8-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 1 is greater than the buffer size

Examples:

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let buf = Buffer.make(0)
Buffer.addInt8(1s, buf)
assert Buffer.getInt8(0, buf) == 1s

Buffer.setInt8

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setInt8 : (index: Number, value: Int8, buffer: Buffer) => Void

Sets a signed 8-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 1 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setInt8(0, 3s, buf)
assert Buffer.getInt8(0, buf) == 3s

Buffer.addInt8

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addInt8 : (value: Int8, buffer: Buffer) => Void

Appends a signed 8-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addInt8(2s, buf)
assert Buffer.getInt8(0, buf) == 2s

Buffer.getUint8

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getUint8 : (index: Number, buffer: Buffer) => Uint8

Gets an unsigned 8-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 1 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addUint8(3us, buf)
assert Buffer.getUint8(0, buf) == 3us

Buffer.setUint8

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setUint8 : (index: Number, value: Uint8, buffer: Buffer) => Void

Sets an unsigned 8-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 1 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setUint8(4us, buf)
assert Buffer.getUint8(0, buf) == 4us

Buffer.addUint8

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addUint8 : (value: Uint8, buffer: Buffer) => Void

Appends an unsigned 8-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addUint8(0us, buf)
assert Buffer.getUint8(0, buf) == 0us

Buffer.getInt16

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getInt16 : (index: Number, buffer: Buffer) => Int16

Gets a signed 16-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 2 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addInt16(1S, buf)
assert Buffer.getInt16(0, buf) == 1S

Buffer.setInt16

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setInt16 : (index: Number, value: Int16, buffer: Buffer) => Void

Sets a signed 16-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 2 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setInt16(5, 1S, buf)
assert Buffer.getInt16(5, buf) == 1S

Buffer.addInt16

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addInt16 : (value: Int16, buffer: Buffer) => Void

Appends a signed 16-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addInt16(2S, buf)
assert Buffer.getInt16(0, buf) == 2S

Buffer.getUint16

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getUint16 : (index: Number, buffer: Buffer) => Uint16

Gets an unsigned 16-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 2 is greater than the buffer size

Examples:

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let buf = Buffer.make(0)
Buffer.addUint16(1uS, buf)
assert Buffer.getUint16(0, buf) == 1uS

Buffer.setUint16

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setUint16 : (index: Number, value: Uint16, buffer: Buffer) => Void

Sets an unsigned 16-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 2 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setUint16(0, 1uS, buf)
assert Buffer.getUint16(0, buf) == 1uS

Buffer.addUint16

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addUint16 : (value: Uint16, buffer: Buffer) => Void

Appends an unsigned 16-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(0)
Buffer.addUint16(0, 2uS, buf)
assert Buffer.getUint16(0, buf) == 2uS

Buffer.getInt32

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getInt32 : (index: Number, buffer: Buffer) => Int32

Gets a signed 32-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(0)
Buffer.addInt32(1l, buf)
assert Buffer.getInt32(0, buf) == 1l

Buffer.setInt32

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setInt32 : (index: Number, value: Int32, buffer: Buffer) => Void

Sets a signed 32-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(64)
Buffer.addString("Hello World", buf)
Buffer.setInt32(3, 1l, buf)
assert Buffer.getInt32(3, buf) == 1l

Buffer.addInt32

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addInt32 : (value: Int32, buffer: Buffer) => Void

Appends a signed 32-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(64)
Buffer.addInt32(1l, buf)
assert Buffer.getInt32(0, buf) == 1l

Buffer.getUint32

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getUint32 : (index: Number, buffer: Buffer) => Uint32

Gets an unsigned 32-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addUint32(1ul, buf)
assert Buffer.getUint32(0, buf) == 1ul

Buffer.setUint32

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setUint32 : (index: Number, value: Uint32, buffer: Buffer) => Void

Sets an unsigned 32-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setUint32(0, 1ul, buf)
assert Buffer.getUint32(0, buf) == 1ul

Buffer.addUint32

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addUint32 : (value: Uint32, buffer: Buffer) => Void

Appends an unsigned 32-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addUint32(1ul, buf)
assert Buffer.getUint32(0, buf) == 1ul

Buffer.getFloat32

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getFloat32 : (index: Number, buffer: Buffer) => Float32

Gets a 32-bit float starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addFloat32(1.0f, buf)
assert Buffer.getFloat32(0, buf) == 1.0f

Buffer.setFloat32

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setFloat32 : (index: Number, value: Float32, buffer: Buffer) => Void

Sets a 32-bit float starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 4 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setFloat32(0, 1.0f, buf)
assert Buffer.getFloat32(0, buf) == 1.0f

Buffer.addFloat32

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addFloat32 : (value: Float32, buffer: Buffer) => Void

Appends a 32-bit float to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addFloat32(1.0f, buf)
assert Buffer.getFloat32(0, buf) == 1.0f

Buffer.getInt64

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getInt64 : (index: Number, buffer: Buffer) => Int64

Gets a signed 64-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addInt64(1L, buf)
assert Buffer.getInt64(0, buf) == 1L

Buffer.setInt64

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setInt64 : (index: Number, value: Int64, buffer: Buffer) => Void

Sets a signed 64-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setInt64(0, 1L, buf)
assert Buffer.getInt64(0, buf) == 1L

Buffer.addInt64

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addInt64 : (value: Int64, buffer: Buffer) => Void

Appends a signed 64-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addInt64(1L, buf)
assert Buffer.getInt64(0, buf) == 1L

Buffer.getUint64

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getUint64 : (index: Number, buffer: Buffer) => Uint64

Gets an unsigned 64-bit integer starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addUint64(1uL, buf)
assert Buffer.getUint64(0, buf) == 1uL

Buffer.setUint64

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setUint64 : (index: Number, value: Uint64, buffer: Buffer) => Void

Sets an unsigned 64-bit integer starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setUint64(0, 1uL, buf)
assert Buffer.getUint64(0, buf) == 1uL

Buffer.addUint64

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addUint64 : (value: Uint64, buffer: Buffer) => Void

Appends an unsigned 64-bit integer to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addUint64(1uL, buf)
assert Buffer.getUint64(0, buf) == 1uL

Buffer.getFloat64

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getFloat64 : (index: Number, buffer: Buffer) => Float64

Gets a 64-bit float starting at the given byte index.

Parameters:

Returns:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addFloat64(1.0F, buf)
assert Buffer.getFloat64(0, buf) == 1.0F

Buffer.setFloat64

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setFloat64 : (index: Number, value: Float64, buffer: Buffer) => Void

Sets a 64-bit float starting at the given byte index.

Parameters:

Throws:

IndexOutOfBounds

• When index is negative
• When index is greater than or equal to the buffer size
• When index + 8 is greater than the buffer size

Examples:

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let buf = Buffer.make(32)
Buffer.addString("Hello World", buf)
Buffer.setFloat64(0, 1.0F, buf)
assert Buffer.getFloat64(0, buf) == 1.0F

Buffer.addFloat64

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addFloat64 : (value: Float64, buffer: Buffer) => Void

Appends a 64-bit float to a buffer.

Parameters:

Examples:

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let buf = Buffer.make(32)
Buffer.addFloat64(1.0F, buf)
assert Buffer.getFloat64(0, buf) == 1.0F