Aggregation Expression - $trunc

Function Build

Build $trunc with the Trunc function from the aggregation package.

// bson.D{bson.E{Key:"truncated", Value:bson.D{bson.E{Key:"$trunc", Value:[]interface {}{"$price", 2}}}}}
result := aggregation.Trunc("truncated", "$price", 2)

Method Build (Builder)

Build $trunc with the Trunc method from aggregation.NewBuilder().

// bson.D{bson.E{Key:"truncated", Value:bson.D{bson.E{Key:"$trunc", Value:[]interface {}{"$price", 2}}}}}
result := aggregation.NewBuilder().
    Trunc("truncated", "$price", 2).
    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.

TruncWithoutKey

This variant is currently available as a builder method.

Method build (Builder):

// bson.D{bson.E{Key:"$trunc", Value:[]any{"$price", 2}}}
expr := aggregation.NewBuilder().
    TruncWithoutKey("$price", 2).
    Build()