Module object/groupBy

groupBy

• groupBy<Fn>(fn: Fn): <Input>(obj: Input) => Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>
• groupBy<Input, Fn>(fn: Fn, obj: Input): Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>

• Creates an object composed of keys generated from the results of running each element of object thru fn. The corresponding value of each key is an array of elements responsible for generating the key.

  example

   groupBy(x => x, { a: 1, b: 1, c: 3});//=> { '1': [1, 1], '3': [3] }
  

  Type parameters

  • Fn: ((value: any, key: number, obj: any[]) => any) | ((value: any, key: number, obj: readonly any[]) => any) | ((value: any, key: any, obj: AnyObj) => any)

  Parameters

  • fn: Fn

    The function to transform value to group key. Receives three argument, value, key, obj.

  Returns <Input>(obj: Input) => Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>

  Returns the composed aggregate object.

  • • <Input>(obj: Input): Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>

    • Type parameters

      • Input: AnyObjOrArr

      Parameters

      • obj: Input

      Returns Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>

• Creates an object composed of keys generated from the results of running each element of object thru fn. The corresponding value of each key is an array of elements responsible for generating the key.

  example

   groupBy(x => x, { a: 1, b: 1, c: 3});//=> { '1': [1, 1], '3': [3] }
  

  Type parameters

  • Input: AnyObjOrArr

  • Fn: ((value: any, key: number, obj: any[]) => any) | ((value: any, key: number, obj: readonly any[]) => any) | ((value: any, key: any, obj: AnyObj) => any)

  Parameters

  • fn: Fn

    The function to transform value to group key. Receives three argument, value, key, obj.

  • obj: Input

    The obj to iterate over.

  Returns Input extends AnyArr ? Record<ReturnType<Fn>, Input> : Record<ReturnType<Fn>, ObjValues<Input>[]>

  Returns the composed aggregate object.