Adjust binary encoding of import/export names#623
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lukewagner merged 3 commits intoWebAssembly:mainfrom Mar 31, 2026
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Adjust binary encoding of import/export names#623lukewagner merged 3 commits intoWebAssembly:mainfrom
lukewagner merged 3 commits intoWebAssembly:mainfrom
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Thanks for the fix (and sorry for the delay)! lgtm with 2 tweaks:
design/mvp/Binary.md
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| versionsuffix' ::= len:<u32> vs:<semversuffix> => (versionsuffix vs) (if len = |vs|) 🔗 | ||
| import ::= in:<importname> ed:<externdesc> => (import in ed) | ||
| export ::= en:<exportname> si:<sortidx> ed?:<externdesc>? => (export en si ed?) | ||
| importname ::= 0x00 len:<u32> in:<importname> => in (if len = |in|) |
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The goal of importname'/exportname' was avoid the confusion in this line, which otherwise looks recursive. One alternative idea is to say <text:importname> (and then update the bullet below which establishes the link of importname to the text format).
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Oh good point, updated back to a ' trailer
The purpose of this commit is to address the discrepancy between the specification and wasm-tools discovered in WebAssembly#622. The history here is: * WebAssembly#222 - historical addition of `(interface "name")` as an import/export name. * WebAssembly#263 - moral revert of the previous change where the kind of name was now encoded in the name instead. At this point `Binary.md` mistakenly no longer reflected what wasm-tools parsed. * WebAssembly#536 - addition of more metadata to import/export names with a discriminator byte that overlapped the previous. This commit is is an adjustment to `Binary.md` to fix these discrepancies. Notably `exportname` and `importname` productions, previously absent. The `exportname'` and `importname'` productions are now renamed to `exportname` and `importname`. Additioanlly the production with `versionsuffix'` have been renumbered to `0x02` while an `0x01` production was added which is the exact same as `0x00` (intended for historical compat). A note was updated in the 1.0 binary adjustments to clean this up. Closes WebAssembly#622
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Co-authored-by: Luke Wagner <mail@lukewagner.name>
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The purpose of this commit is to address the discrepancy between the specification and wasm-tools discovered in #622. The history here is:
(interface "name")as an import/export name.Binary.mdmistakenly no longer reflected what wasm-tools parsed.This commit is is an adjustment to
Binary.mdto fix these discrepancies. Notablyexportnameandimportnameproductions, previously absent. Theexportname'andimportname'productions are now renamed toexportnameandimportname. Additioanlly the production withversionsuffix'have been renumbered to0x02while an0x01production was added which is the exact same as0x00(intended for historical compat). A note was updated in the 1.0 binary adjustments to clean this up.Closes #622