Add splat (#786)

Author: martinholters

Project.toml

@@ -1,6 +1,6 @@
 name = "Compat"
 uuid = "34da2185-b29b-5c13-b0c7-acf172513d20"
-version = "4.5.0"
+version = "4.6.0"
 
 [deps]
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"

README.md

@@ -70,7 +70,7 @@ changes in `julia`.
 
 ## Supported features
 
-* `Splat(f)` which is equivalent to `args -> f(args...)`. ([#42717]) (since Compat 4.5.0) 
+* `splat(f)` which is equivalent to `args -> f(args...)`. ([#42717], [#48038]) (since Compat 4.6.0) (Note: for historical reasons, `Compat` on Julia before v1.9 also exports `Splat`; its usage is discouraged, however.)
 
 * `Compat.@assume_effects setting... ex` overrides the compiler's effect modeling for the method definition `ex` on Julia versions that support this feature. Julia version without support just pass back `ex`. ([#43852]) (since Compat 4.4.0)
 
@@ -142,6 +142,7 @@ is at least this version by `VERSION >= v"X.Y.Z-aaa+NNNN"`.
 Note that you should specify the correct minimum version for `Compat` in the
 `[compat]` section of your `Project.toml`, as given in above list.
 
+[`@bdf9ead9`]: https://github.com/JuliaLang/julia/commit/bdf9ead91e5a8dfd91643a17c1626032faada329
 [#29901]: https://github.com/JuliaLang/julia/issues/29901
 [#35316]: https://github.com/JuliaLang/julia/issues/35316
 [#36229]: https://github.com/JuliaLang/julia/issues/36229
@@ -157,6 +158,8 @@ Note that you should specify the correct minimum version for `Compat` in the
 [#41312]: https://github.com/JuliaLang/julia/issues/41312
 [#42125]: https://github.com/JuliaLang/julia/issues/42125
 [#42351]: https://github.com/JuliaLang/julia/issues/42351
-[#43354]: https://github.com/JuliaLang/julia/issues/43354
+[#42717]: https://github.com/JuliaLang/julia/issues/42717
 [#43334]: https://github.com/JuliaLang/julia/issues/43334
-[`@bdf9ead9`]: https://github.com/JuliaLang/julia/commit/bdf9ead91e5a8dfd91643a17c1626032faada329
+[#43354]: https://github.com/JuliaLang/julia/issues/43354
+[#43852]: https://github.com/JuliaLang/julia/issues/43852
+[#48038]: https://github.com/JuliaLang/julia/issues/48038

src/Compat.jl

@@ -616,44 +616,27 @@ if VERSION < v"1.9.0-DEV.1163"
 
     _empty_stack(_...) = throw(ArgumentError("`stack` on an empty collection is not allowed"))
 end
-                                
-@static if VERSION < v"1.9.0-DEV.513"
-    # https://github.com/JuliaLang/julia/pull/42717
-    export Splat
-
-    struct Splat{F} <: Function
-        f::F
-        Splat(f) = new{Core.Typeof(f)}(f)
+
+if v"1.10.0-" <= VERSION < v"1.10.0-DEV.360" || VERSION < v"1.9.0-beta3"
+    if VERSION < v"1.9.0-DEV.513"
+        # https://github.com/JuliaLang/julia/pull/42717
+        export Splat # Base does not export this, but we have to keep it for compatibility
+
+        struct Splat{F} <: Function
+            f::F
+            Splat(f) = new{Core.Typeof(f)}(f)
+        end
+
+        (s::Splat)(args) = s.f(args...)
+        Base.print(io::IO, s::Splat) = print(io, "splat(", s.f, ')')
+        Base.show(io::IO, s::Splat) = print(io, s)
+        Base.show(io::IO, ::MIME"text/plain", s::Splat) = show(io, s)
     end
 
-    (s::Splat)(args) = s.f(args...)
-    Base.print(io::IO, s::Splat) = print(io, "Splat(", s.f, ')')
-    Base.show(io::IO, s::Splat) = print(io, s)
-    Base.show(io::IO, ::MIME"text/plain", s::Splat) = show(io, s)
-    @doc """
-    Splat(f)
-Equivalent to
-```julia
-    my_splat(f) = args->f(args...)
-```
-i.e. given a function returns a new function that takes one argument and splats
-its argument into the original function. This is useful as an adaptor to pass
-a multi-argument function in a context that expects a single argument, but
-passes a tuple as that single argument. Additionally has pretty printing.
-# Example usage:
-```jldoctest
-julia> map(Base.Splat(+), zip(1:3,4:6))
-3-element Vector{Int64}:
- 5
- 7
- 9
-julia> my_add = Base.Splat(+)
-Splat(+)
-julia> my_add((1,2,3))
-6
-```
-""" Splat
-end 
+    # https://github.com/JuliaLang/julia/pull/48038
+    export splat
+    splat(f) = Splat(f)
+end
 
 include("deprecated.jl")
 

test/runtests.jl

@@ -578,8 +578,16 @@ end
     end
 end
 
-@testset "Splat" begin
-    @test Splat(+)((1,2,3)) == 6
-    @test repr(Splat(+)) == "Splat(+)"
-    @test repr(MIME"text/plain"(), Splat(+)) == "Splat(+)"
+@testset "splat" begin
+    @test splat(+)((1,2,3)) == 6
+
+    if v"1.10.0-" <= VERSION < v"1.10.0-DEV.360" ||
+        v"1.9.0-DEV.513" <= VERSION < v"1.9.0-beta3"
+        # these versions of Base export Splat (which we use) but pretty-print with capital `S`
+        @test repr(splat(+)) == "Splat(+)"
+        @test repr(MIME"text/plain"(), splat(+)) == "Splat(+)"
+    else
+        @test repr(splat(+)) == "splat(+)"
+        @test repr(MIME"text/plain"(), splat(+)) == "splat(+)"
+    end
 end