Add intersect(::AbstractRange, ::AbstractVector)

Closes #41759
JuliaLang · Aug 3, 2021 · b865814 · b865814
1 parent 4f28e6f
commit b865814
Show file tree

Hide file tree

Showing 2 changed files with 10 additions and 0 deletions.
diff --git a/base/range.jl b/base/range.jl
@@ -1151,6 +1151,13 @@ function intersect(r1::AbstractRange, r2::AbstractRange, r3::AbstractRange, r::A
     i
 end
 
+function intersect(r::AbstractRange, vec::AbstractVector)
+    common = Iterators.filter(x -> x ∈ r, vec)
+    seen = Set{eltype(vec)}(common)
+    return vectorfilter(_shrink_filter!(seen), common)
+end
+intersect(vec::AbstractVector, r::AbstractRange) = intersect(r, vec)
+
 # _findin (the index of intersection)
 function _findin(r::AbstractRange{<:Integer}, span::AbstractUnitRange{<:Integer})
     local ifirst

diff --git a/test/ranges.jl b/test/ranges.jl
@@ -403,6 +403,9 @@ end
         @test intersect(1:3, 2) === intersect(2, 1:3) === 2:2
         @test intersect(1.0:3.0, 2) == intersect(2, 1.0:3.0) == [2.0]
 
+        @test intersect(1:typemax(Int), [1, 3]) === [1, 3]
+        @test intersect([1, 3], 1:typemax(Int)) === [1, 3]
+
         @testset "Support StepRange with a non-numeric step" begin
             start = Date(1914, 7, 28)
             stop = Date(1918, 11, 11)