Document why the wasm_abi attributes are deprecated - #91
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The README said what to use instead but never why, which is what #86 asked for. Explains the infallible-ABI mechanism, quotes wasm-bindgen's own destructor warning, and points at the observed failure mode. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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The README says the
wasm_abiattributes are deprecated and what to use instead, but never why — which is what @siefkenj asked for in #86 ("We deprecatedfrom_wasm_abiin the README, but I think the explanation of why is missing").Adds a short section explaining the mechanism:
FromWasmAbi::from_abireturnsSelf, notResult, so a serde failure at the ABI boundary has onlythrow_strto fall back on — which, as wasm-bindgen's own docs warn, does not run destructors. Everything alive at that point leaks, including arguments converted before the failing one.Ts<T>keeps the boundary infallible and moves deserialization into the function body, where it is an ordinaryResult.Since
src/lib.rsincludes the README as crate docs, this also lands on docs.rs.The CONTRIBUTING note is a trap I hit writing this: every
```rustblock in the README is compiled as a doctest through that same include.🤖 Generated with Claude Code