1.4.5: Add reverse encoders for packed repeated fields. #108
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Like the Vector encoders but unlike the forward-order Foldable encoders they avoid the need to save elements to the stack before encoding them, instead immediately encoding the final element as the first step. However, the new encoders lack the special optimizations around size checks that are possible for the Vector encoders, which have advance knowledge of the number of elements. This change also avoids compiler warnings in benchmark code.
They are no more unsafe than unsafeFromLazyByteString.
riz0id
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Mar 18, 2025
riz0id
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riz0id
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j6carey
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When encoding from a Data.Vector.Vector this library would already encode from right to left in order to avoid saving all but the final element to the stack. The relevant encoders would also exploit the fact that vectors have known element counts in order to consolidate size checks and associated reallocations when encoding packed fields with fixed-width elements.
This change adds new encoders that generalize those two optimizations to other types of container such as
Data.Sequence.Seq. When a container does not support right-to-left iteration and/or length prediction (for example, a standard list), these new encoders still support them as efficiently as is practical, given those restrictions.Also added:
bytesIfNonempty,etaMessageBuilder,repeatedMessageBuilder,unsafeFromByteString,unsafeFromShortByteString.