$$distinct

Returns a distinct array (repeating elements removed, only primitive values are supported if no by is specified)

Usage

{
  "$$distinct": [ /* values */ ],
  "by": /* Transformer */
}

"$$distinct([by]):{input}"

Returns

array (same items type as input)

Arguments

Argument	Type	Values	Required / Default Value	Description
Primary	array		Yes	Array of elements
by	Transformer(##current)	Input is ##current (current element)	"##current"	A mapping for each element to distinct by (instead of the whole element)

Examples

Input

Definition

Output

[
  "a",
  "b",
  "b",
  "c",
  "b"
]

{ 
  "$$distinct": "$" 
}

[
  "a",
  "b",
  "c"
]

[ 
  "a",
  1,
  false,
  "b",
  "c",
  "b",
  1,
  false,
  false
]

{ 
  "$$distinct": "$" 
}

[
  "a",
  1,
  false,
  "b",
  "c"
]

[
  "a",
  "a",
  null,
  null,
  "a",
  null
]

{
  "$$distinct": "$" 
}

[ 
  "a", 
  null
]

[
  { "a": 1 },
  { "a": 1 },
  { "a": 1 }
]

{ 
  "$$distinct": "$" 
}

[
  { "a": 1 }
]

[
  [ "a", 1 ],
  [ "a", 2 ],
  [ "a", 1 ],
  [ "a", 1 ]
]

{ 
  "$$distinct": "$" 
}

[
  [ "a", 1 ],
  [ "a", 2 ]
]

[
  { "a": 1 },
  { 
    "a": 1,
    "b": 1
  },
  { "a": 1,
    "b": 2
  },
  { "a": 2,
    "b": 1
  }
]

{ 
  "$$distinct": "$", 
  "by": "##current.a" 
}

[
  { "a": 1 },
  { 
    "a": 2,
    "b": 1
  }
]

[
  { "a": 1 },
  { 
    "a": 1 ,
    "b": 1
  },
  {
    "a": 1,
    "b": 2
  },
  {
    "a": 2,
    "b": 1
  }
]

{ 
  "$$distinct": "$", 
  "by": "##current.b" 
}

[
  { "a": 1 },
  { 
    "a": 1, 
    "b": 1
  },
  { 
    "a": 1, 
    "b": 2
  }
]