Aggregation Expression - $slice

SliceWithPosition builds a $slice expression with a starting offset.

Function Build

Build $slice with the Slice function from the aggregation package.

// bson.D{bson.E{Key:"topScores", Value:bson.D{bson.E{Key:"$slice", Value:[]interface {}{"$scores", 3}}}}}
result := aggregation.Slice("topScores", "$scores", 3)

Method Build (Builder)

Build $slice with the SliceWithPosition method from aggregation.NewBuilder().

// bson.D{bson.E{Key:"topScores", Value:bson.D{bson.E{Key:"$slice", Value:[]interface {}{"$scores", 3}}}}}
result := aggregation.NewBuilder().
    SliceWithPosition("topScores", "$scores", 1, 3).
    Build()

Build Without Key

When an expression needs to be passed as an argument to another expression, use a WithoutKey variant to build an expression fragment without an output field name.

SliceWithoutKey

Function build:

// bson.D{bson.E{Key:"$slice", Value:[]any{"$scores", 3}}}
expr := aggregation.SliceWithoutKey("$scores", 3)

Method build (Builder):

// bson.D{bson.E{Key:"$slice", Value:[]any{"$scores", 3}}}
expr := aggregation.NewBuilder().
    SliceWithoutKey("$scores", 3).
    Build()

SliceWithPositionWithoutKey

Function build:

// bson.D{bson.E{Key:"$slice", Value:[]any{"$scores", 1, 3}}}
expr := aggregation.SliceWithPositionWithoutKey("$scores", 1, 3)

Method build (Builder):

// bson.D{bson.E{Key:"$slice", Value:[]any{"$scores", 1, 3}}}
expr := aggregation.NewBuilder().
    SliceWithPositionWithoutKey("$scores", 1, 3).
    Build()