Keep the underlying storage capacity when clearing the FlatBufferBuil…

…der. Gives a significant performance boost for serialisation of many small messages. (google#7250)
MegEngine · Apr 16, 2022 · e37156a · e37156a
1 parent a10b0e5
commit e37156a
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/swift/Sources/FlatBuffers/FlatBufferBuilder.swift b/swift/Sources/FlatBuffers/FlatBufferBuilder.swift
@@ -127,8 +127,8 @@ public struct FlatBufferBuilder {
  mutating public func clear() {
  _minAlignment = 0
  isNested = false
- stringOffsetMap = [:]
- _vtables = []
+ stringOffsetMap.removeAll(keepingCapacity: true)
+ _vtables.removeAll(keepingCapacity: true)
  _vtableStorage.clear()
  _bb.clear()
  }