Add NEWS.md entry for

NEWS.md

@@ -37,6 +37,8 @@ New library functions
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 * `Iterators.flatmap` was added ([#44792]).
+* New helper `Splat(f)` which acts like `x -> f(x...)`, with pretty printing for
+  inspecting which function `f` was originally wrapped. ([#42717])
 
 Library changes
 ---------------
@@ -48,7 +50,6 @@ Library changes
 * Predicate function negation `!f` now returns a composed function `(!) ∘ f` instead of an anonymous function ([#44752]).
 * `RoundFromZero` now works for non-`BigFloat` types ([#41246]).
 
-
 Standard library changes
 ------------------------
 
@@ -110,6 +111,7 @@ Standard library changes
 Deprecated or removed
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+* Unexported `splat` is deprecated in favor of exported `Splat`, which has pretty printing of the wrapped function. ([#42717])
 
 External dependencies
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