Struct MemoryType 

pub struct MemoryType { /* private fields */ }

A descriptor for a WebAssembly memory type.

Memories are described in units of pages (64KB) and represent contiguous chunks of addressable memory.

Implementations

impl MemoryType

pub fn new(minimum: u32, maximum: Option<u32>) -> MemoryType

Available on crate feature runtime only.

Creates a new descriptor for a 32-bit WebAssembly memory given the specified limits of the memory.

The minimum and maximum values here are specified in units of WebAssembly pages, which are 64KiB by default. Use MemoryTypeBuilder if you want a non-default page size.

Panics

Panics if the minimum is greater than the maximum or if the minimum or maximum number of pages can result in a byte size that is not addressable with a 32-bit integer.

pub fn new64(minimum: u64, maximum: Option<u64>) -> MemoryType

Available on crate feature runtime only.

Creates a new descriptor for a 64-bit WebAssembly memory given the specified limits of the memory.

The minimum and maximum values here are specified in units of WebAssembly pages, which are 64KiB by default. Use MemoryTypeBuilder if you want a non-default page size.

Note that 64-bit memories are part of the memory64 proposal for WebAssembly which is not fully standardized yet.

Panics

Panics if the minimum is greater than the maximum or if the minimum or maximum number of pages can result in a byte size that is not addressable with a 64-bit integer.

pub fn shared(minimum: u32, maximum: u32) -> MemoryType

Available on crate feature runtime only.

Creates a new descriptor for shared WebAssembly memory given the specified limits of the memory.

The minimum and maximum values here are specified in units of WebAssembly pages, which are 64KiB by default. Use MemoryTypeBuilder if you want a non-default page size.

Note that shared memories are part of the threads proposal for WebAssembly which is not fully standardized yet.

Panics

Panics if the minimum is greater than the maximum or if the minimum or maximum number of pages can result in a byte size that is not addressable with a 32-bit integer.

pub fn builder() -> MemoryTypeBuilder

Available on crate feature runtime only.

Creates a new MemoryTypeBuilder to configure all the various knobs of the final memory type being created.

This is a convenience function for MemoryTypeBuilder::new.

pub fn is_64(&self) -> bool

Available on crate feature runtime only.

Returns whether this is a 64-bit memory or not.

Note that 64-bit memories are part of the memory64 proposal for WebAssembly which is not standardized yet.

pub fn is_shared(&self) -> bool

Available on crate feature runtime only.

Returns whether this is a shared memory or not.

Note that shared memories are part of the threads proposal for WebAssembly which is not standardized yet.

pub fn minimum(&self) -> u64

Available on crate feature runtime only.

Returns minimum number of WebAssembly pages this memory must have.

Note that the return value, while a u64, will always fit into a u32 for 32-bit memories.

pub fn maximum(&self) -> Option<u64>

Available on crate feature runtime only.

Returns the optionally-specified maximum number of pages this memory can have.

If this returns None then the memory is not limited in size.

Note that the return value, while a u64, will always fit into a u32 for 32-bit memories.

pub fn page_size(&self) -> u64

Available on crate feature runtime only.

This memory’s page size, in bytes.

pub fn page_size_log2(&self) -> u8

Available on crate feature runtime only.

The log2 of this memory’s page size, in bytes.

pub fn default_value(&self, store: impl AsContextMut) -> Result<RuntimeMemory>

Available on crate feature runtime only.

Construct a new memory import initialized to this memory type’s default state

Returns a host Memory in the given store with the configured initial page size and zeroed contents.

Trait Implementations

impl Clone for MemoryType

Available on crate feature runtime only.

fn clone(&self) -> MemoryType

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MemoryType

Available on crate feature runtime only.

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

Formats the value using the given formatter.

impl From<MemoryType> for ExternType

Available on crate feature runtime only.

fn from(ty: MemoryType) -> ExternType

Converts to this type from the input type.

impl Hash for MemoryType

Available on crate feature runtime only.

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for MemoryType

Available on crate feature runtime only.

fn eq(&self, other: &MemoryType) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for MemoryType

Available on crate feature runtime only.

impl StructuralPartialEq for MemoryType

Available on crate feature runtime only.