data oriented programming

Data is immutable.

Data is explicit.

Data is long live than the program.

value semantics

copy-on-write

inout 引數

code:swift

func f(v: inout V) {

v.x += 1

}

var v: V = …

f(&v)

code:javascript

v = produce(v, v => {

v.x += 1;

});

mutating func

inout な self

code:swift

extention V {

mutationg func inc() {

self.x += 1

}

}

var v: V = …

v.inc()

computed property は inout