imeian at gmail.com (2019-09-06T09:24:09.039Z)
Yes of course I could use the /= operator in this simple example, but not in more complex operations. About itself in a property, it's correct : I mean itself to refer to the actual value, the value being from a variable or an object property doesn't matter. itself would not be a this equivalent, so whenever itself is used it refers to the actual value we are assigning
Yes of course I could use the /= operator in this simple example, but not in more complex operations. About itself in a property, it's correct : I mean itself to refer to the actual value, the value being from a variable or an object property doesn't matter. itself would not be a this equivalent, so whenever itself is used it refers to the actual value we are assigning Le ven. 6 sept. 2019 à 10:34, Cyril Auburtin <cyril.auburtin at gmail.com> a écrit : > You could currently do > ```js > object.child.property /= 5 > ``` > > with destructuring: > ```js > const {child: {subchild}, child} = state; > > return { > ...state, > child: { > ...child, > subchild: { > ...subchild, > property: subchild.property + 1 > } > } > } > ``` > > or do-expressions: > ```js > return { > ...state, > child: do { > const {child} = state; > return { > ...child, > subchild: do { > const {subchild} = child; > return { > ...subchild, > property: subchild.property + 1 > }; > } > }; > } > } > ``` > > note: your `property: itself + 1` looks incorrect, since you probably mean > to increment the `property` property > > On Fri, Sep 6, 2019 at 9:36 AM Imeian . <imeian at gmail.com> wrote: > >> When we need to change a value using the old value : >> >> variable = itself + 5 // instead of >> variable = variable + 5 >> >> object.child.property = itself / 5 // instead of >> object.child.property = object.child.property / 5 >> >> Changing a value in nested objects is a pain, like Redux states for eg. >> >> return { >> ...state, >> child: { >> ...state.child, >> subchild: { >> ...state.child.subchild, >> property: state.child.subchild.property + 1 >> } >> } >> } >> >> would then be >> >> return { >> ...state, >> child: { >> ...itself, >> subchild: { >> ...itself, >> property: itself + 1 >> } >> } >> } >> >> >> _______________________________________________ >> es-discuss mailing list >> es-discuss at mozilla.org >> https://mail.mozilla.org/listinfo/es-discuss >> > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20190906/4fcde00b/attachment-0001.html>