From bc4e8ce32c9289ba936b1e1d6a54b72cbb238080 Mon Sep 17 00:00:00 2001
From: Takafumi Arakaki <aka.tkf@gmail.com>
Date: Tue, 15 Oct 2019 21:58:52 -0700
Subject: [PATCH] =?UTF-8?q?Add=20ASCII=20alias=20`compose`=20of=20`?=
 =?UTF-8?q?=E2=88=98`?=
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---
 NEWS.md           | 2 ++
 base/exports.jl   | 1 +
 base/operators.jl | 7 ++++++-
 test/operators.jl | 1 +
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/NEWS.md b/NEWS.md
index f7afd2de594345..b8f07fe06135d6 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -11,6 +11,8 @@ New language features
 * Function composition now supports multiple functions: `∘(f, g, h) = f ∘ g ∘ h`
 and splatting `∘(fs...)` for composing an iterable collection of functions ([#33568]). 
 
+* Function composition `∘` now has an ASCII alias `compose`.
+
 Language changes
 ----------------
 
diff --git a/base/exports.jl b/base/exports.jl
index 49063720c14c47..80fd9d6c76fb10 100644
--- a/base/exports.jl
+++ b/base/exports.jl
@@ -763,6 +763,7 @@ export
 # misc
     atexit,
     atreplinit,
+    compose,
     exit,
     ntuple,
 
diff --git a/base/operators.jl b/base/operators.jl
index 232f6407ed6f5d..61913fd50bc66e 100644
--- a/base/operators.jl
+++ b/base/operators.jl
@@ -823,6 +823,7 @@ julia> [1:5;] |> x->x.^2 |> sum |> inv
 
 """
     f ∘ g
+    compose(f, g)
 
 Compose functions: i.e. `(f ∘ g)(args...)` means `f(g(args...))`. The `∘` symbol can be
 entered in the Julia REPL (and most editors, appropriately configured) by typing `\\circ<tab>`.
@@ -832,7 +833,7 @@ The prefix form supports composition of multiple functions: `∘(f, g, h) = f 
 and splatting `∘(fs...)` for composing an iterable collection of functions.
 
 !!!compat "Julia 1.4"
-    Multiple function composition requires at least Julia 1.4.    
+    Multiple function composition and ASCII alias `compose` require at least Julia 1.4.
 
 # Examples
 ```jldoctest
@@ -851,10 +852,14 @@ julia> fs = [
 
 julia> ∘(fs...)(3)
 3.0
+
+julia> ∘(fs...) === compose(fs...)
+true
 ```
 """
 ∘(f, g) = (x...)->f(g(x...))
 ∘(f, g, h...) = ∘(f ∘ g, h...)
+const compose = ∘
 
 """
     !f::Function
diff --git a/test/operators.jl b/test/operators.jl
index 58102d7d65a328..699f98aa388f28 100644
--- a/test/operators.jl
+++ b/test/operators.jl
@@ -111,6 +111,7 @@ Base.promote_rule(::Type{T19714}, ::Type{Int}) = T19714
     @test ∘(x -> x-2, x -> x-3, x -> x+5)(7) == 7
     fs = [x -> x[1:2], uppercase, lowercase]
     @test ∘(fs...)("ABC") == "AB"
+    @test ∘(fs...) === compose(fs...)
 end
 @testset "function negation" begin
     str = randstring(20)