Struct Wasm

pub struct Wasm { /* private fields */ }

Implementations

impl Wasm

pub fn alloc(&self, bytes: usize) -> *mut u8

Allocates n bytes of memory from the WASM heap and returns the address of the first byte in the block

impl Wasm

pub fn dealloc(&self, ptr: *mut u8)

Frees memory returned by alloc()

impl Wasm

pub fn heap8u(&self) -> Uint8Array

View into the wasm memory reprsented as unsigned 8-bit integers

It is important never to hold on to objects returned from methods like heap8u() long-term, as they may be invalidated if the heap grows. It is acceptable to hold the reference for a brief series of calls, so long as those calls are guaranteed not to allocate memory on the WASM heap, but it should never be cached for later use.

impl Wasm

pub fn cstr_to_js(&self, ptr: *const c_char) -> String

Expects its argument to be a pointer into the WASM heap memory which refers to a NUL-terminated C-style string encoded as UTF-8.

impl Wasm

pub fn poke(&self, from: &[u8], dst: *mut u8)

Write buffer to wasm pointer

pub unsafe fn peek<T>(&self, from: *mut u8, dst: &mut T)

Read T size buffer from wasm pointer

pub unsafe fn peek_buf(&self, from: *mut u8, len: usize, dst: &mut [u8])

Read specified size buffer from wasm pointer

Methods from Deref<Target = SQLiteHandle>

pub fn capi(&self) -> CApi

pub fn wasm(&self) -> Wasm

Methods from Deref<Target = JsValue>

pub const NULL: JsValue

pub const UNDEFINED: JsValue

pub const TRUE: JsValue

pub const FALSE: JsValue

pub fn as_f64(&self) -> Option<f64>

Returns the f64 value of this JS value if it’s an instance of a number.

If this JS value is not an instance of a number then this returns None.

pub fn is_string(&self) -> bool

Tests whether this JS value is a JS string.

pub fn as_string(&self) -> Option<String>

If this JS value is a string value, this function copies the JS string value into Wasm linear memory, encoded as UTF-8, and returns it as a Rust String.

To avoid the copying and re-encoding, consider the JsString::try_from() function from js-sys instead.

If this JS value is not an instance of a string or if it’s not valid utf-8 then this returns None.

UTF-16 vs UTF-8

JavaScript strings in general are encoded as UTF-16, but Rust strings are encoded as UTF-8. This can cause the Rust string to look a bit different than the JS string sometimes. For more details see the documentation about the str type which contains a few caveats about the encodings.

pub fn as_bool(&self) -> Option<bool>

Returns the bool value of this JS value if it’s an instance of a boolean.

If this JS value is not an instance of a boolean then this returns None.

pub fn is_null(&self) -> bool

Tests whether this JS value is null

pub fn is_undefined(&self) -> bool

Tests whether this JS value is undefined

pub fn is_symbol(&self) -> bool

Tests whether the type of this JS value is symbol

pub fn is_object(&self) -> bool

Tests whether typeof self == "object" && self !== null.

pub fn is_array(&self) -> bool

Tests whether this JS value is an instance of Array.

pub fn is_function(&self) -> bool

Tests whether the type of this JS value is function.

pub fn is_bigint(&self) -> bool

Tests whether the type of this JS value is bigint.

pub fn js_typeof(&self) -> JsValue

Applies the unary typeof JS operator on a JsValue.

MDN documentation

pub fn js_in(&self, obj: &JsValue) -> bool

Applies the binary in JS operator on the two JsValues.

MDN documentation

pub fn is_truthy(&self) -> bool

Tests whether the value is “truthy”.

pub fn is_falsy(&self) -> bool

Tests whether the value is “falsy”.

pub fn loose_eq(&self, other: &JsValue) -> bool

Compare two JsValues for equality, using the == operator in JS.

MDN documentation

pub fn bit_not(&self) -> JsValue

Applies the unary ~ JS operator on a JsValue.

MDN documentation

pub fn unsigned_shr(&self, rhs: &JsValue) -> u32

Applies the binary >>> JS operator on the two JsValues.

MDN documentation

pub fn checked_div(&self, rhs: &JsValue) -> JsValue

Applies the binary / JS operator on two JsValues, catching and returning any RangeError thrown.

MDN documentation

pub fn pow(&self, rhs: &JsValue) -> JsValue

Applies the binary ** JS operator on the two JsValues.

MDN documentation

pub fn lt(&self, other: &JsValue) -> bool

Applies the binary < JS operator on the two JsValues.

MDN documentation

pub fn le(&self, other: &JsValue) -> bool

Applies the binary <= JS operator on the two JsValues.

MDN documentation

pub fn ge(&self, other: &JsValue) -> bool

Applies the binary >= JS operator on the two JsValues.

MDN documentation

pub fn gt(&self, other: &JsValue) -> bool

Applies the binary > JS operator on the two JsValues.

MDN documentation

pub fn unchecked_into_f64(&self) -> f64

Applies the unary + JS operator on a JsValue. Can throw.

MDN documentation

Trait Implementations

impl AsRef<JsValue> for Wasm

fn as_ref(&self) -> &JsValue

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<SQLiteHandle> for Wasm

fn as_ref(&self) -> &SQLiteHandle

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<Wasm> for Wasm

fn as_ref(&self) -> &Wasm

Converts this type into a shared reference of the (usually inferred) input type.

impl Deref for Wasm

type Target = SQLiteHandle

The resulting type after dereferencing.

fn deref(&self) -> &SQLiteHandle

Dereferences the value.

impl From<JsValue> for Wasm

fn from(obj: JsValue) -> Wasm

Converts to this type from the input type.

impl From<Wasm> for JsValue

fn from(obj: Wasm) -> JsValue

Converts to this type from the input type.

impl From<Wasm> for SQLiteHandle

fn from(obj: Wasm) -> SQLiteHandle

Converts to this type from the input type.

impl FromWasmAbi for Wasm

type Abi = <JsValue as FromWasmAbi>::Abi

The Wasm ABI type that this converts from when coming back out from the ABI boundary.

unsafe fn from_abi(js: Self::Abi) -> Self

Recover a Self from Self::Abi.

impl<'a> IntoWasmAbi for &'a Wasm

type Abi = <&'a JsValue as IntoWasmAbi>::Abi

The Wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl IntoWasmAbi for Wasm

type Abi = <JsValue as IntoWasmAbi>::Abi

The Wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl JsCast for Wasm

fn instanceof(val: &JsValue) -> bool

Performs a dynamic instanceof check to see whether the JsValue provided is an instance of this type.

fn unchecked_from_js(val: JsValue) -> Self

Performs a zero-cost unchecked conversion from a JsValue into an instance of Self

fn unchecked_from_js_ref(val: &JsValue) -> &Self

Performs a zero-cost unchecked conversion from a &JsValue into an instance of &Self.

fn has_type<T>(&self) -> bool

where T: JsCast,

Test whether this JS value has a type T.

fn dyn_into<T>(self) -> Result<T, Self>

where T: JsCast,

Performs a dynamic cast (checked at runtime) of this value into the target type T.

fn dyn_ref<T>(&self) -> Option<&T>

where T: JsCast,

Performs a dynamic cast (checked at runtime) of this value into the target type T.

fn unchecked_into<T>(self) -> T

where T: JsCast,

Performs a zero-cost unchecked cast into the specified type.

fn unchecked_ref<T>(&self) -> &T

where T: JsCast,

Performs a zero-cost unchecked cast into a reference to the specified type.

fn is_instance_of<T>(&self) -> bool

where T: JsCast,

Test whether this JS value is an instance of the type T.

fn is_type_of(val: &JsValue) -> bool

Performs a dynamic check to see whether the JsValue provided is a value of this type.

impl LongRefFromWasmAbi for Wasm

type Abi = <JsValue as LongRefFromWasmAbi>::Abi

Same as RefFromWasmAbi::Abi

type Anchor = Wasm

Same as RefFromWasmAbi::Anchor

unsafe fn long_ref_from_abi(js: Self::Abi) -> Self::Anchor

Same as RefFromWasmAbi::ref_from_abi

impl OptionFromWasmAbi for Wasm

fn is_none(abi: &Self::Abi) -> bool

Tests whether the argument is a “none” instance. If so it will be deserialized as None, and otherwise it will be passed to FromWasmAbi.

impl<'a> OptionIntoWasmAbi for &'a Wasm

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option.

impl OptionIntoWasmAbi for Wasm

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option.

impl RefFromWasmAbi for Wasm

type Abi = <JsValue as RefFromWasmAbi>::Abi

The Wasm ABI type references to Self are recovered from.

type Anchor = ManuallyDrop<Wasm>

The type that holds the reference to Self for the duration of the invocation of the function that has an &Self parameter. This is required to ensure that the lifetimes don’t persist beyond one function call, and so that they remain anonymous.

unsafe fn ref_from_abi(js: Self::Abi) -> Self::Anchor

Recover a Self::Anchor from Self::Abi.

impl WasmDescribe for Wasm

fn describe()