javascript - Create arrays of duplicates js -


for example: have array looks this:

let arr = [{     name: "peter" }, {     name: "peter" }, {     name: "john" }, {     name: "peter" }, {     name: "sarah" }, {     name: "john" }]

i need create array, this:

let duparray = [     [{         name: "peter"     }, {         name: "peter"     }, {         name: "peter"     }],     [{         name: "john"     }, {         name: "john"     }],     [{         name: "sarah"     }] ]

again, it's not duplicating, it's creating new array duplicates grouped.

reduce them map , values():

let arr = [{    name: "peter"  }, {    name: "peter"  }, {    name: "john"  }, {    name: "peter"  }, {    name: "sarah"  }, {    name: "john"  }];    let duparr =       [...arr.reduce((a,b) =>           a.set(b.name , (a.get(b.name) || []).concat(b)),       new map()).values()];    console.log(duparr);


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