From fa799fb1156cfbc7df8505463cccbc1331b3546d Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Sat, 3 Dec 2022 21:25:53 +0000
Subject: [PATCH 1/5] Start Bi-infinite ranges

---
 src/InfiniteArrays.jl   |  2 +-
 src/biinfrange.jl       | 21 +++++++++++++++++++++
 test/test_biinfrange.jl |  8 ++++++++
 3 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 src/biinfrange.jl
 create mode 100644 test/test_biinfrange.jl

diff --git a/src/InfiniteArrays.jl b/src/InfiniteArrays.jl
index abf3a8c..7765b6c 100644
--- a/src/InfiniteArrays.jl
+++ b/src/InfiniteArrays.jl
@@ -211,7 +211,7 @@ end
     return LazyArrays.searchsortedlast_recursive(n, x, args...)
 end
 
-
+include("biinfrange.jl")
 
 
 end # module
diff --git a/src/biinfrange.jl b/src/biinfrange.jl
new file mode 100644
index 0000000..bdc8f52
--- /dev/null
+++ b/src/biinfrange.jl
@@ -0,0 +1,21 @@
+"""
+BiInfUnitRange()
+
+Represent -∞:∞ with offset indexing
+"""
+struct BiInfUnitRange{T<:Real} <: AbstractInfUnitRange{T} end
+
+BiInfUnitRange() = BiInfUnitRange{Int}()
+
+AbstractArray{T}(a::BiInfUnitRange) where T<:Real = BiInfUnitRange{T}(a)
+AbstractVector{T}(a::BiInfUnitRange) where T<:Real = BiInfUnitRange{T}(a)
+
+unitrange(a::BiInfUnitRange) = a
+Base.has_offset_axes(::BiInfUnitRange) = true
+
+getindex(v::BiInfUnitRange{T}, i::Integer) where T = convert(T, i)
+axes(::BiInfUnitRange) = (BiInfUnitRange(),)
+first(::BiInfUnitRange) = -∞
+show(io::IO, ::BiInfUnitRange{Int}) = print(io, "BiInfUnitRange()")
+
+getindex(r::BiInfUnitRange{T}, s::AbstractUnitRange{<:Integer}) where T = convert(AbstractVector{T}, s)
\ No newline at end of file
diff --git a/test/test_biinfrange.jl b/test/test_biinfrange.jl
new file mode 100644
index 0000000..0a2b3d3
--- /dev/null
+++ b/test/test_biinfrange.jl
@@ -0,0 +1,8 @@
+using InfiniteArrays, Base64, Test
+using InfiniteArrays: BiInfUnitRange
+
+@testset "-∞:∞" begin
+    r = BiInfUnitRange()
+    @test stringmime("text/plain", r) == "BiInfUnitRange()"
+    
+end
\ No newline at end of file

From 85b07b44732dab1bee37760aaa78ef76da83efee Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Sun, 14 Dec 2025 07:39:38 +0000
Subject: [PATCH 2/5] Update test_biinfrange.jl

---
 test/test_biinfrange.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/test_biinfrange.jl b/test/test_biinfrange.jl
index 0a2b3d3..ca35566 100644
--- a/test/test_biinfrange.jl
+++ b/test/test_biinfrange.jl
@@ -4,5 +4,5 @@ using InfiniteArrays: BiInfUnitRange
 @testset "-∞:∞" begin
     r = BiInfUnitRange()
     @test stringmime("text/plain", r) == "BiInfUnitRange()"
-    
+    @test Fill(1, (r,))[-5] == 1
 end
\ No newline at end of file

From 34f57c3a2d00a9d075a634b936924d23bda5e403 Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Sun, 14 Dec 2025 07:49:41 +0000
Subject: [PATCH 3/5] try to fix printing

---
 src/biinfrange.jl       | 1 +
 src/infrange.jl         | 1 +
 test/runtests.jl        | 4 ++++
 test/test_biinfrange.jl | 1 +
 4 files changed, 7 insertions(+)

diff --git a/src/biinfrange.jl b/src/biinfrange.jl
index bdc8f52..28ba42c 100644
--- a/src/biinfrange.jl
+++ b/src/biinfrange.jl
@@ -14,6 +14,7 @@ unitrange(a::BiInfUnitRange) = a
 Base.has_offset_axes(::BiInfUnitRange) = true
 
 getindex(v::BiInfUnitRange{T}, i::Integer) where T = convert(T, i)
+getindex(v::BiInfUnitRange{T}, i::RealInfinity) where T = i
 axes(::BiInfUnitRange) = (BiInfUnitRange(),)
 first(::BiInfUnitRange) = -∞
 show(io::IO, ::BiInfUnitRange{Int}) = print(io, "BiInfUnitRange()")
diff --git a/src/infrange.jl b/src/infrange.jl
index b551551..61ea4c1 100644
--- a/src/infrange.jl
+++ b/src/infrange.jl
@@ -29,6 +29,7 @@ _range(a::Real,          ::Nothing,         ::Nothing, len::InfiniteCardinal{0})
 _range(a::AbstractFloat, ::Nothing,         ::Nothing, len::InfiniteCardinal{0}) = _range(a, oftype(a, 1),   nothing, len)
 _range(a::T, st::T, ::Nothing, ::InfiniteCardinal{0}) where T<:IEEEFloat = InfStepRange{T,T}(a, st)
 _range(a::T, st::T, ::Nothing, ::InfiniteCardinal{0}) where T<:AbstractFloat = InfStepRange{T,T}(a, st)
+_range(a::Infinities.AllInfinities, ::Nothing, ::Nothing, length::Int) = Fill(a, length)
 range_start_step_length(a, st, ::InfiniteCardinal{0}) = InfStepRange(a, st)
 range_start_step_length(a::Real, st::IEEEFloat, len::InfiniteCardinal{0}) = range_start_step_length(promote(a, st)..., len)
 range_start_step_length(a::IEEEFloat, st::Real, len::InfiniteCardinal{0}) = range_start_step_length(promote(a, st)..., len)
diff --git a/test/runtests.jl b/test/runtests.jl
index cdeebe4..aa49614 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -564,6 +564,10 @@ end
         @test_throws ArgumentError [1:∞; [1.0]; 1:∞]
         @test_throws ArgumentError [1:∞; 1; [1]]
     end
+
+    @testset "range from ∞" begin
+        @test range(ℵ₀; length=5) ≡ Fill(ℵ₀, 5)
+    end
 end
 
 @testset "fill" begin
diff --git a/test/test_biinfrange.jl b/test/test_biinfrange.jl
index ca35566..c8b7ded 100644
--- a/test/test_biinfrange.jl
+++ b/test/test_biinfrange.jl
@@ -5,4 +5,5 @@ using InfiniteArrays: BiInfUnitRange
     r = BiInfUnitRange()
     @test stringmime("text/plain", r) == "BiInfUnitRange()"
     @test Fill(1, (r,))[-5] == 1
+    @test exp.(r)[-3] == exp(-3)
 end
\ No newline at end of file

From a33a187b6adff1cd0b362b4e452ad6fbf0d452d2 Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Mon, 15 Dec 2025 09:08:22 +0000
Subject: [PATCH 4/5] Update runtests.jl

---
 test/runtests.jl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/runtests.jl b/test/runtests.jl
index aa49614..268a28a 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1300,7 +1300,8 @@ end
     @test !checkbounds(Bool, r, Fill(true, 1))
 end
 
+include("test_biinfrange.jl")
 include("test_infconv.jl")
 include("test_infblock.jl")
 include("test_infbanded.jl")
-include("test_infblockbanded.jl")
+include("test_infblockbanded.jl")
\ No newline at end of file

From 7649693c6818295059b938bd96a769bbcd86291f Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Mon, 15 Dec 2025 10:44:54 +0000
Subject: [PATCH 5/5] add print

---
 src/InfiniteArrays.jl |  2 +-
 src/biinfrange.jl     | 82 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 82 insertions(+), 2 deletions(-)

diff --git a/src/InfiniteArrays.jl b/src/InfiniteArrays.jl
index 2a92ec8..11bcb60 100644
--- a/src/InfiniteArrays.jl
+++ b/src/InfiniteArrays.jl
@@ -14,7 +14,7 @@ import Base: *, +, -, /, <, ==, >, \, ≤, ≥, (:), @propagate_inbounds,
              searchsortedfirst, searchsortedlast, setindex!, show, show_circular, show_delim_array, sign,
              signbit, similar, size, sort, sort!, step, sum, tail,
              to_shape, transpose, unaliascopy, union, unitrange_last, unsafe_convert, unsafe_indices, unsafe_length,
-             vcat, zeros, copyto!, range_start_step_length
+             vcat, zeros, copyto!, range_start_step_length, undef_ref_str, alignment
 
 if VERSION ≥ v"1.11.0-DEV.21"
    using LinearAlgebra: UpperOrLowerTriangular
diff --git a/src/biinfrange.jl b/src/biinfrange.jl
index 28ba42c..8647741 100644
--- a/src/biinfrange.jl
+++ b/src/biinfrange.jl
@@ -19,4 +19,84 @@ axes(::BiInfUnitRange) = (BiInfUnitRange(),)
 first(::BiInfUnitRange) = -∞
 show(io::IO, ::BiInfUnitRange{Int}) = print(io, "BiInfUnitRange()")
 
-getindex(r::BiInfUnitRange{T}, s::AbstractUnitRange{<:Integer}) where T = convert(AbstractVector{T}, s)
\ No newline at end of file
+getindex(r::BiInfUnitRange{T}, s::AbstractUnitRange{<:Integer}) where T = convert(AbstractVector{T}, s)
+
+
+
+function Base._print_matrix(io, @nospecialize(X::AbstractVecOrMat), pre, sep, post, hdots, vdots, ddots, hmod, vmod, rowsA::BiInfUnitRange, colsA)
+    hmod, vmod = Int(hmod)::Int, Int(vmod)::Int
+    ncols, idxlast = length(colsA), last(colsA)
+    if !(get(io, :limit, false)::Bool)
+        screenheight = screenwidth = typemax(Int)
+    else
+        sz = displaysize(io)::Tuple{Int,Int}
+        screenheight, screenwidth = sz[1] - 4, sz[2]
+    end
+    screenwidth -= length(pre)::Int + length(post)::Int
+    presp = repeat(" ", length(pre)::Int)  # indent each row to match pre string
+    postsp = ""
+    @assert textwidth(hdots) == textwidth(ddots)
+    sepsize = length(sep)::Int
+    m, n = length(rowsA), length(colsA)
+    # To figure out alignments, only need to look at as many rows as could
+    # fit down screen. If screen has at least as many rows as A, look at A.
+    # If not, then we only need to look at the first and last chunks of A,
+    # each half a screen height in size.
+    quarterheight = div(screenheight,4)
+    halfheight = 2quarterheight+1
+    rowsA = -quarterheight:quarterheight
+    # Similarly for columns, only necessary to get alignments for as many
+    # columns as could conceivably fit across the screen
+    maxpossiblecols = div(screenwidth, 1+sepsize)
+    if n > maxpossiblecols
+        colsA = [colsA[(0:maxpossiblecols-1) .+ firstindex(colsA)]; colsA[(end-maxpossiblecols+1):end]]
+    else
+        colsA = [colsA;]
+    end
+    A = alignment(io, X, rowsA, colsA, screenwidth, screenwidth, sepsize, ncols)
+    # Nine-slicing is accomplished using print_matrix_row repeatedly
+    if n <= length(A) # rows don't fit, cols do, so only vertical ellipsis
+        print_matrix_vdots(io, vdots, A, sep, vmod, 1, false)
+        print(io, postsp * '\n')
+        for i in rowsA
+            print(io, i == first(rowsA) ? pre : presp)
+            i == 0 && print(io, "\e[1m")
+            print_matrix_row(io, X,A,i,colsA,sep,idxlast)
+            i == 0 && print(io, "\e[0m")
+            print(io, i == last(rowsA) ? post : postsp)
+            if i != rowsA[end] || i == rowsA[halfheight]; println(io); end
+            if i == rowsA[halfheight]
+                print(io, i == first(rowsA) ? pre : presp)
+                print_matrix_vdots(io, vdots, A, sep, vmod, 1, false)
+                print(io, i == last(rowsA) ? post : postsp * '\n')
+            end
+        end
+    else # neither rows nor cols fit, so use all 3 kinds of dots
+        c = div(screenwidth-length(hdots)::Int+1,2)+1
+        Ralign = reverse(alignment(io, X, rowsA, reverse(colsA), c, c, sepsize, ncols))
+        c = screenwidth - sum(map(sum,Ralign)) - (length(Ralign)-1)*sepsize - length(hdots)::Int
+        Lalign = alignment(io, X, rowsA, colsA, c, c, sepsize, ncols)
+        r = mod((length(Ralign)-n+1),vmod) # where to put dots on right half
+        for i in rowsA
+            print(io, i == first(rowsA) ? pre : presp)
+            print_matrix_row(io, X,Lalign,i,colsA[1:length(Lalign)],sep,idxlast)
+            print(io, (i - first(rowsA)) % hmod == 0 ? hdots : repeat(" ", length(hdots)::Int))
+            print_matrix_row(io, X,Ralign,i,(n-length(Ralign)).+colsA,sep,idxlast)
+            print(io, i == last(rowsA) ? post : postsp)
+            if i != rowsA[end] || i == rowsA[halfheight]; println(io); end
+            if i == rowsA[halfheight]
+                print(io, i == first(rowsA) ? pre : presp)
+                print_matrix_vdots(io, vdots, Lalign, sep, vmod, 1, true)
+                print(io, ddots)
+                print_matrix_vdots(io, vdots, Ralign, sep, vmod, r, false)
+                print(io, i == last(rowsA) ? post : postsp * '\n')
+            end
+        end
+    end
+    if isempty(rowsA)
+        print(io, pre)
+        print(io, vdots)
+        length(colsA) > 1 && print(io, "    ", ddots)
+        print(io, post)
+    end
+end