Struct worker::Env

Invokes JSON.stringify on this value and then parses the resulting JSON into an arbitrary Rust value.

This function will first call JSON.stringify on the JsValue itself. The resulting string is then passed into Rust which then parses it as JSON into the resulting value.

Usage of this API requires activating the serde-serialize feature of the wasm-bindgen crate.

Errors

Returns any error encountered when parsing the JSON into a T.

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.

Tests whether this JS value is a JS 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.

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.

Tests whether this JS value is null

Tests whether this JS value is undefined

Tests whether the type of this JS value is symbol

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

Tests whether the type of this JS value is function.

Tests whether the type of this JS value is function.

Applies the unary typeof JS operator on a JsValue.

MDN documentation

Applies the binary in JS operator on the two JsValues.

MDN documentation

Tests whether the value is “truthy”.

Tests whether the value is “falsy”.

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

MDN documentation

Applies the unary ~ JS operator on a JsValue.

MDN documentation

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

MDN documentation

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

MDN documentation

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

MDN documentation

Applies the binary < JS operator on the two JsValues.

MDN documentation

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

MDN documentation

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

MDN documentation

Applies the binary > JS operator on the two JsValues.

MDN documentation

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

MDN documentation