pub fn append_string( &self, name: &str, value: &str ) {
        js! { @(no_return)
            @{self}.append(@{name}, @{value});
        }
    }
/// Appends a new value onto an existing key, or adds the key if it does not already exist.
///
/// [(JavaScript docs)](https://developer.mozilla.org/en-US/docs/Web/API/FormData/append)
// https://xhr.spec.whatwg.org/#dom-formdata-append
Appends a new value onto an existing key, or adds the key if it does not already exist.
Appends a new value onto an existing key or adds the key if it does not already exist .
pub fn append_string( &self, name: &str, value: &str ) {
        js! { @(no_return)
            @{self}.append(@{name}, @{value});
        }
    }
pub fn append_string ( & self , name : & str , value : & str ) { js ! { ( no_return ) { self } append ( { name } { value } ) } }
Appends a new value onto an existing key, or adds the key if it does not already exist.
Appends a new value onto an existing key or adds the key if it does not already exist .
&self
name
&str
value
&str
&self
name
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