Struct wasm_encoder::DataSection

pub struct DataSection { /* private fields */ }

An encoder for the data section.

Data sections are only supported for modules.

Example

use wasm_encoder::{
    ConstExpr, DataSection, Instruction, MemorySection, MemoryType,
    Module,
};

let mut memory = MemorySection::new();
memory.memory(MemoryType {
    minimum: 1,
    maximum: None,
    memory64: false,
    shared: false,
    page_size_log2: None,
});

let mut data = DataSection::new();
let memory_index = 0;
let offset = ConstExpr::i32_const(42);
let segment_data = b"hello";
data.active(memory_index, &offset, segment_data.iter().copied());

let mut module = Module::new();
module
    .section(&memory)
    .section(&data);

let wasm_bytes = module.finish();

Implementations

impl DataSection

pub fn new() -> Self

Create a new data section encoder.

pub fn len(&self) -> u32

The number of data segments in the section.

pub fn is_empty(&self) -> bool

Determines if the section is empty.

pub fn segment<D>(&mut self, segment: DataSegment<'_, D>) -> &mut Self

where D: IntoIterator<Item = u8>, D::IntoIter: ExactSizeIterator,

Define a data segment.

pub fn active<D>( &mut self, memory_index: u32, offset: &ConstExpr, data: D, ) -> &mut Self

where D: IntoIterator<Item = u8>, D::IntoIter: ExactSizeIterator,

Define an active data segment.

pub fn passive<D>(&mut self, data: D) -> &mut Self

where D: IntoIterator<Item = u8>, D::IntoIter: ExactSizeIterator,

Define a passive data segment.

Passive data segments are part of the bulk memory proposal.

pub fn raw(&mut self, already_encoded_data_segment: &[u8]) -> &mut Self

Copy an already-encoded data segment into this data section.

Trait Implementations

impl Clone for DataSection

fn clone(&self) -> DataSection

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DataSection

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DataSection

fn default() -> DataSection

Returns the “default value” for a type.

impl Encode for DataSection

fn encode(&self, sink: &mut Vec<u8>)

Encode the type into the given byte sink.

impl Section for DataSection

fn id(&self) -> u8

Gets the section identifier for this section.

fn append_to(&self, dst: &mut Vec<u8>)

Appends this section to the specified destination list of bytes.