core: add fmt::Debug
impl to dyn Value
s
#696
Merged
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Motivation
Currently, the only way to interact with
Value
s is to record them witha visitor. In the most common case, where typed data is not needed,
Value
s are recorded with theirfmt::Debug
implementations — avisitor which does not implement the
record_${TYPE}
traits willautomatically fall back to recording all primitive value types with
Debug
. However, implementing a visitor requires a bit of boilerplate:an entire trait implementation has to be written, and a visitor object
passed to
record
.Solution
This branch hopes to simplify this common case by adding a
Debug
implementation to all
dyn Value
trait objects. This is equivalentto a visitor that only implements
record_debug
, but requiring lessboilerplate.