From f9c7716f7528992d4c3ed4569c36048bcdb96df8 Mon Sep 17 00:00:00 2001
From: Arnav Sood <soodarnav01@gmail.com>
Date: Fri, 15 Feb 2019 12:11:35 -0800
Subject: [PATCH] define fallback `inv(x::AbstractIrrational)` (#31068)

close #30882
---
 base/irrationals.jl | 3 +++
 test/numbers.jl     | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/base/irrationals.jl b/base/irrationals.jl
index 8249dc07ce773..1c3557cc5581c 100644
--- a/base/irrationals.jl
+++ b/base/irrationals.jl
@@ -185,3 +185,6 @@ function alignment(io::IO, x::AbstractIrrational)
     m === nothing ? (length(sprint(show, x, context=ctx, sizehint=0)), 0) :
     (length(m.captures[1]), length(m.captures[2]))
 end
+
+# inv
+inv(x::AbstractIrrational) = 1/x
diff --git a/test/numbers.jl b/test/numbers.jl
index 952cf67c36d03..d7a22b892edd3 100644
--- a/test/numbers.jl
+++ b/test/numbers.jl
@@ -1038,6 +1038,10 @@ end
     end
 end
 
+@testset "Irrational Inverses, Issue #30882" begin
+    @test @inferred(inv(π)) ≈ 0.3183098861837907
+end
+
 @testset "Irrationals compared with Rationals and Floats" begin
     @test Float64(pi,RoundDown) < pi
     @test Float64(pi,RoundUp) > pi