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fix: fromStringImpl is the 4-ary function its Fn4 declaration requires - #9
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The entry was a chain of nested single-argument closures, but runFn4 calls the underlying implementation n-ary — fn(a, b, c, d) — and Lua silently drops the surplus arguments on a 1-ary function, so Data.Number.fromString returned the inner closure instead of a Maybe Number on every PureScript call path (the runtime runFn4 fallback and the compiler uncurried lift alike). Flatten the implementation to a single 4-ary function and pin the n-ary convention in the regression guard. Refs purescript-lua/purescript-lua#186.
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Problem
fromStringImplis declaredFn4 String (Number -> Boolean) (forall a. a -> Maybe a) (forall a. Maybe a) (Maybe Number), but the Lua entry was a chain of nested single-argument closures, a shape it has carried since the fork's initial import.runFn4(and the compiler's uncurried lift) call the implementation n-ary,fn(a, b, c, d), and Lua silently drops surplus arguments on a 1-ary function, soData.Number.fromStringreturned the inner closure instead of aMaybe Numberon every PureScript call path in the released v9.1.4.Found by the FFI audit in purescript-lua/purescript-lua#186. It stayed invisible because the regression guard called the entry curried,
fromStringImpl(s)(isFinite)(just)(nothing), which pinned the wrong convention, and no compiler golden exercisesfromString.Change
src/Data/Number.lua: flattenfromStringImplto a single 4-ary function; the parse logic (parseFloat prefix tolerance,isFiniteguard,Nothingon failure: the #93 semantics) is unchanged.test/regression/number.lua: the guard calls the entry n-ary, the wayrunFn4does. It was red against the old shape (all 7 fromString checks) and is green after.Verification
scripts/testgreen (Format and Number suites). Reproduction against the released code through the realrunFn4fallback of the functions fork:runFn4(fromStringImpl)("1.5")(isFinite)(Just)(Nothing)had typefunctionbefore and isJust 1.5after; the direct post-lift callfromStringImpl("1.5", isFinite, Just, Nothing)behaves identically.Suggested release: patch (v9.1.5) plus a package-set bump.
Refs purescript-lua/purescript-lua#186.