From 5039668467aab5a84833b92a35e0ad167c40993a Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Wed, 21 Jun 2023 14:41:38 -0400
Subject: [PATCH 01/15] add rand dispatch for tuple types

---
 stdlib/Random/src/generation.jl | 3 +++
 stdlib/Random/test/runtests.jl  | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index cc9840f678413..ab3c08a676c20 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -167,6 +167,9 @@ function rand(r::AbstractRNG, ::SamplerType{T}) where {T<:AbstractChar}
     (c < 0xd800) ? T(c) : T(c+0x800)
 end
 
+### random tuples
+
+rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple} = T(rand.(Ref(r), T.parameters))
 
 ## Generate random integer within a range
 
diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index eb5ae32965469..21bb91babe18d 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -333,7 +333,7 @@ end
 for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
     ftypes = [Float16, Float32, Float64, FakeFloat64, BigFloat]
     cftypes = [ComplexF16, ComplexF32, ComplexF64, ftypes...]
-    types = [Bool, Char, BigFloat, Base.BitInteger_types..., ftypes...]
+    types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ftypes...]
     randset = Set(rand(Int, 20))
     randdict = Dict(zip(rand(Int,10), rand(Int, 10)))
     collections = [BitSet(rand(1:100, 20))          => Int,
@@ -401,6 +401,7 @@ for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
     end
     for f! in [rand!, randn!, randexp!]
         for T in functypes[f!]
+            (T <: Tuple) && continue
             X = T == Bool ? T[0,1] : T[0,1,2]
             for A in (Vector{T}(undef, 5),
                       Matrix{T}(undef, 2, 3),

From c54a9694ae85be1209cff6a5cab14d949c6b2695 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Thu, 22 Jun 2023 08:48:23 -0400
Subject: [PATCH 02/15] remove allocating broadcast

---
 stdlib/Random/src/generation.jl | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index ab3c08a676c20..284752278b7a9 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -169,7 +169,9 @@ end
 
 ### random tuples
 
-rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple} = T(rand.(Ref(r), T.parameters))
+function rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple}
+    ntuple(i -> rand(r, T.parameters[i]), length(T.parameters))
+end
 
 ## Generate random integer within a range
 

From dd5bfe19f81ebe996565414f5e23d6de29b5b222 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Tue, 27 Jun 2023 14:24:30 -0400
Subject: [PATCH 03/15] use opt. generated ntuple & add @inferred test

---
 stdlib/Random/src/generation.jl | 2 +-
 stdlib/Random/test/runtests.jl  | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index 284752278b7a9..6729c0438a042 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -170,7 +170,7 @@ end
 ### random tuples
 
 function rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple}
-    ntuple(i -> rand(r, T.parameters[i]), length(T.parameters))
+    ntuple(i -> rand(r, T.parameters[i]), Val(length(T.parameters)))
 end
 
 ## Generate random integer within a range
diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index 21bb91babe18d..9ef690e3078ef 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -336,6 +336,10 @@ for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
     types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ftypes...]
     randset = Set(rand(Int, 20))
     randdict = Dict(zip(rand(Int,10), rand(Int, 10)))
+
+    randwidetup = Tuple{Bool, Char, Vararg{Tuple{Int, Float64}, 14}}
+    @inferred rand(rng..., randwidetup)
+
     collections = [BitSet(rand(1:100, 20))          => Int,
                    randset                          => Int,
                    GenericSet(randset)              => Int,

From 57f45e7bf3f8e109a2cf4fc6cc36cb7b1798f791 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Tue, 27 Jun 2023 16:31:05 -0400
Subject: [PATCH 04/15] remove access to internal properties

---
 stdlib/Random/src/generation.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index 6729c0438a042..f3f3671ade876 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -170,7 +170,7 @@ end
 ### random tuples
 
 function rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple}
-    ntuple(i -> rand(r, T.parameters[i]), Val(length(T.parameters)))
+    ntuple(i -> rand(r, fieldtype(T, i)), Val(fieldcount(T)))
 end
 
 ## Generate random integer within a range

From 59a07bb629a3eed969a6c3a0af58cb5e0f625498 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Mon, 3 Jul 2023 16:45:02 -0400
Subject: [PATCH 05/15] add rational rand dispatch

---
 stdlib/Random/src/Random.jl     | 27 ++++++++++++++++++++++-----
 stdlib/Random/src/generation.jl | 10 ++++++++++
 stdlib/Random/test/runtests.jl  |  3 ++-
 3 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index 78d4f15e2beac..efc8756095f82 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -313,12 +313,26 @@ include("XoshiroSimd.jl")
 Pick a random element or array of random elements from the set of values specified by `S`;
 `S` can be
 
-* an indexable collection (for example `1:9` or `('x', "y", :z)`),
-* an `AbstractDict` or `AbstractSet` object,
+* an indexable collection (for example `1:9` or `('x', "y", :z)`)
+
+* an `AbstractDict` or `AbstractSet` object
+
 * a string (considered as a collection of characters), or
-* a type: the set of values to pick from is then equivalent to `typemin(S):typemax(S)` for
-  integers (this is not applicable to [`BigInt`](@ref)), to ``[0, 1)`` for floating
-  point numbers and to ``[0, 1)+i[0, 1)`` for complex floating point numbers;
+
+* a supported type: the set of values to pick from is then equivalent to
+
+  + `typemin(S):typemax(S)` for concrete integer types (excepting [`BigInt`](@ref) which is not supported)
+
+  + ``[0, 1)`` for concrete floating point types
+
+  + `rand(T) + rand(T) * im` for concrete complex types `Complex{T}`
+
+  + `rand(T) // rand(T)` for concrete rational types `Rational{T}`
+
+  + a valid Unicode scalar for any `<:AbstractChar` type
+
+* a Tuple type of supported types
+
 
 `S` defaults to [`Float64`](@ref).
 When only one argument is passed besides the optional `rng` and is a `Tuple`, it is interpreted
@@ -330,6 +344,9 @@ See also [`randn`](@ref) for normally distributed numbers, and [`rand!`](@ref) a
 !!! compat "Julia 1.1"
     Support for `S` as a tuple requires at least Julia 1.1.
 
+!!! compat "Julia 1.11"
+    Support for `S` as a `Rational` or `Tuple` type requires at least Julia 1.11.
+
 # Examples
 ```julia-repl
 julia> rand(Int, 2)
diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index f3f3671ade876..a64cd61721d65 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -159,6 +159,16 @@ rand_generic(r::AbstractRNG, ::Type{Int64})  = rand(r, UInt64) % Int64
 rand(r::AbstractRNG, ::SamplerType{Complex{T}}) where {T<:Real} =
     complex(rand(r, T), rand(r, T))
 
+### random rational numbers
+
+function rand(r::AbstractRNG, ::SamplerType{Rational{T}}) where {T<:Integer}
+    den = rand(r, T)
+    while iszero(den) || isequal(den, typemin(T))
+        den = rand(r, T)
+    end
+    return Rational(rand(r, T), den)
+end
+
 ### random characters
 
 # returns a random valid Unicode scalar value (i.e. 0 - 0xd7ff, 0xe000 - # 0x10ffff)
diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index 9ef690e3078ef..e0e4dde2e4ae7 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -333,7 +333,8 @@ end
 for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
     ftypes = [Float16, Float32, Float64, FakeFloat64, BigFloat]
     cftypes = [ComplexF16, ComplexF32, ComplexF64, ftypes...]
-    types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ftypes...]
+    ritypes = [Rational{T} for T in Base.BitInteger_types]
+    types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ritypes..., ftypes...]
     randset = Set(rand(Int, 20))
     randdict = Dict(zip(rand(Int,10), rand(Int, 10)))
 

From ef602c976c684d1ff8d4ac0611cfd732d5ec91b0 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Mon, 3 Jul 2023 16:52:50 -0400
Subject: [PATCH 06/15] add to news

---
 NEWS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/NEWS.md b/NEWS.md
index 18a8f89f6d382..8899083db845c 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -46,6 +46,7 @@ Standard library changes
 #### Profile
 
 #### Random
+* `rand` now supports sampling over `Rational` types and `Tuple` types ([#50251]).
 
 #### REPL
 

From 030cc1683d59c56fa979534b9ec0a263e6fdc5f7 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Tue, 4 Jul 2023 10:00:44 -0400
Subject: [PATCH 07/15] remove rational rand

---
 NEWS.md                         |  2 +-
 stdlib/Random/src/Random.jl     |  4 +---
 stdlib/Random/src/generation.jl | 10 ----------
 stdlib/Random/test/runtests.jl  |  3 +--
 4 files changed, 3 insertions(+), 16 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 8899083db845c..e42d008cd9285 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -46,7 +46,7 @@ Standard library changes
 #### Profile
 
 #### Random
-* `rand` now supports sampling over `Rational` types and `Tuple` types ([#50251]).
+* `rand` now supports sampling over `Tuple` types ([#50251]).
 
 #### REPL
 
diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index efc8756095f82..a76ee3cebe7b7 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -327,8 +327,6 @@ Pick a random element or array of random elements from the set of values specifi
 
   + `rand(T) + rand(T) * im` for concrete complex types `Complex{T}`
 
-  + `rand(T) // rand(T)` for concrete rational types `Rational{T}`
-
   + a valid Unicode scalar for any `<:AbstractChar` type
 
 * a Tuple type of supported types
@@ -345,7 +343,7 @@ See also [`randn`](@ref) for normally distributed numbers, and [`rand!`](@ref) a
     Support for `S` as a tuple requires at least Julia 1.1.
 
 !!! compat "Julia 1.11"
-    Support for `S` as a `Rational` or `Tuple` type requires at least Julia 1.11.
+    Support for `S` as a `Tuple` type requires at least Julia 1.11.
 
 # Examples
 ```julia-repl
diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index a64cd61721d65..f3f3671ade876 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -159,16 +159,6 @@ rand_generic(r::AbstractRNG, ::Type{Int64})  = rand(r, UInt64) % Int64
 rand(r::AbstractRNG, ::SamplerType{Complex{T}}) where {T<:Real} =
     complex(rand(r, T), rand(r, T))
 
-### random rational numbers
-
-function rand(r::AbstractRNG, ::SamplerType{Rational{T}}) where {T<:Integer}
-    den = rand(r, T)
-    while iszero(den) || isequal(den, typemin(T))
-        den = rand(r, T)
-    end
-    return Rational(rand(r, T), den)
-end
-
 ### random characters
 
 # returns a random valid Unicode scalar value (i.e. 0 - 0xd7ff, 0xe000 - # 0x10ffff)
diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index e0e4dde2e4ae7..9ef690e3078ef 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -333,8 +333,7 @@ end
 for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
     ftypes = [Float16, Float32, Float64, FakeFloat64, BigFloat]
     cftypes = [ComplexF16, ComplexF32, ComplexF64, ftypes...]
-    ritypes = [Rational{T} for T in Base.BitInteger_types]
-    types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ritypes..., ftypes...]
+    types = [Bool, Char, BigFloat, Tuple{Bool, Tuple{Int, Char}}, Base.BitInteger_types..., ftypes...]
     randset = Set(rand(Int, 20))
     randdict = Dict(zip(rand(Int,10), rand(Int, 10)))
 

From 41da3823a0cd9053ed5b3635388d20f4973b845d Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Sun, 3 Sep 2023 19:24:01 -0400
Subject: [PATCH 08/15] faster sampler generation

---
 stdlib/Random/docs/src/index.md |  2 +-
 stdlib/Random/src/Random.jl     |  6 ++++--
 stdlib/Random/src/generation.jl | 13 +++++++++++--
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/stdlib/Random/docs/src/index.md b/stdlib/Random/docs/src/index.md
index e344e47947440..7ef885775c58f 100644
--- a/stdlib/Random/docs/src/index.md
+++ b/stdlib/Random/docs/src/index.md
@@ -81,7 +81,7 @@ Random.MersenneTwister
 Random.RandomDevice
 ```
 
-## Hooking into the `Random` API
+## [Hooking into the `Random` API](@id rand-api-hook)
 
 There are two mostly orthogonal ways to extend `Random` functionalities:
 1) generating random values of custom types
diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index a76ee3cebe7b7..b4f3231b3398f 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -319,7 +319,7 @@ Pick a random element or array of random elements from the set of values specifi
 
 * a string (considered as a collection of characters), or
 
-* a supported type: the set of values to pick from is then equivalent to
+* a type (and corresponding domain) from the list below
 
   + `typemin(S):typemax(S)` for concrete integer types (excepting [`BigInt`](@ref) which is not supported)
 
@@ -329,7 +329,9 @@ Pick a random element or array of random elements from the set of values specifi
 
   + a valid Unicode scalar for any `<:AbstractChar` type
 
-* a Tuple type of supported types
+* a user-defined type and domain; for implementation guidance please see [Hooking into the `Random` API](@ref rand-api-hook)
+
+* a Tuple type `T` where each parameter of `T` is itself a sampleable type; return a value of type `T``
 
 
 `S` defaults to [`Float64`](@ref).
diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index f3f3671ade876..47507e139f987 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -169,8 +169,17 @@ end
 
 ### random tuples
 
-function rand(r::AbstractRNG, ::SamplerType{T}) where {T<:Tuple}
-    ntuple(i -> rand(r, fieldtype(T, i)), Val(fieldcount(T)))
+function Sampler(RNG::Type{<:AbstractRNG}, t::Type{T}, n::Repetition) where {T <: Tuple}
+    tail_sp_ = Sampler(RNG, Tuple{fieldtypes(t)[2:end]...}, n)
+    SamplerTag{t}((Sampler(RNG, fieldtype(t, 1), n), tail_sp_.data...))
+end
+
+function Sampler(RNG::Type{<:AbstractRNG}, t::Type{Tuple{Vararg{T, N}}}, n::Repetition) where {T, N}
+    SamplerTag{t}((Sampler(RNG, T, n),))
+end
+
+function rand(rng::AbstractRNG, sp::SamplerTag{T}) where T<:Tuple
+    ntuple(i -> rand(rng, sp.data[min(i, length(sp.data))]), Val{fieldcount(T)}())
 end
 
 ## Generate random integer within a range

From 07ffd9a6f563a2b90e431ba1c5628e5ac9776dab Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Sun, 3 Sep 2023 20:23:40 -0400
Subject: [PATCH 09/15] get rid of implicit `convert`

---
 stdlib/Random/src/generation.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index 47507e139f987..0ff6b9267fcc5 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -179,7 +179,7 @@ function Sampler(RNG::Type{<:AbstractRNG}, t::Type{Tuple{Vararg{T, N}}}, n::Repe
 end
 
 function rand(rng::AbstractRNG, sp::SamplerTag{T}) where T<:Tuple
-    ntuple(i -> rand(rng, sp.data[min(i, length(sp.data))]), Val{fieldcount(T)}())
+    ntuple(i -> rand(rng, sp.data[min(i, length(sp.data))]), Val{fieldcount(T)}())::T
 end
 
 ## Generate random integer within a range

From b2ba3b189ef4fcc6623718018ed3676835cc5483 Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Sun, 3 Sep 2023 20:50:56 -0400
Subject: [PATCH 10/15] fix double backticks

---
 stdlib/Random/src/Random.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index b4f3231b3398f..8bbaeb2f4958f 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -323,7 +323,7 @@ Pick a random element or array of random elements from the set of values specifi
 
   + `typemin(S):typemax(S)` for concrete integer types (excepting [`BigInt`](@ref) which is not supported)
 
-  + ``[0, 1)`` for concrete floating point types
+  + `[0, 1)` for concrete floating point types
 
   + `rand(T) + rand(T) * im` for concrete complex types `Complex{T}`
 

From 73dc45e9abd58815e4f0a1a563f7b9a5a087f49a Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Thu, 7 Sep 2023 17:52:09 -0400
Subject: [PATCH 11/15] use Base.tail

---
 stdlib/Random/src/generation.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index 0ff6b9267fcc5..293ce2f27ce21 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -170,7 +170,7 @@ end
 ### random tuples
 
 function Sampler(RNG::Type{<:AbstractRNG}, t::Type{T}, n::Repetition) where {T <: Tuple}
-    tail_sp_ = Sampler(RNG, Tuple{fieldtypes(t)[2:end]...}, n)
+    tail_sp_ = Sampler(RNG, Tuple{Base.tail(fieldtypes(t))...}, n)
     SamplerTag{t}((Sampler(RNG, fieldtype(t, 1), n), tail_sp_.data...))
 end
 

From cf5e0265f9c3fd16db501448288b8b05f3d8972f Mon Sep 17 00:00:00 2001
From: Andy Dienes <andydienes@gmail.com>
Date: Thu, 14 Sep 2023 17:08:16 -0400
Subject: [PATCH 12/15] update docs, apply code review, add tests

---
 stdlib/Random/src/Random.jl     | 15 ++++++++-------
 stdlib/Random/src/generation.jl | 10 +++++-----
 stdlib/Random/test/runtests.jl  |  4 ++++
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index 8bbaeb2f4958f..e5e2b4251bde6 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -319,19 +319,20 @@ Pick a random element or array of random elements from the set of values specifi
 
 * a string (considered as a collection of characters), or
 
-* a type (and corresponding domain) from the list below
+* a type from the list below, corresponding to the specified set of values
 
-  + `typemin(S):typemax(S)` for concrete integer types (excepting [`BigInt`](@ref) which is not supported)
+  + concrete integer types sample from `typemin(S):typemax(S)` (excepting [`BigInt`](@ref) which is not supported)
 
-  + `[0, 1)` for concrete floating point types
+  + concrete floating point types sample from `[0, 1)`
 
-  + `rand(T) + rand(T) * im` for concrete complex types `Complex{T}`
+  + concrete complex types `Complex{T}` sample from `rand(T) + rand(T) * im`
 
-  + a valid Unicode scalar for any `<:AbstractChar` type
+  + all `<:AbstractChar` types sample from the set of valid Unicode scalars
 
-* a user-defined type and domain; for implementation guidance please see [Hooking into the `Random` API](@ref rand-api-hook)
+  + a user-defined type and set of values; for implementation guidance please see [Hooking into the `Random` API](@ref rand-api-hook)
 
-* a Tuple type `T` where each parameter of `T` is itself a sampleable type; return a value of type `T``
+  + `S` can also be a tuple type of known size and where each parameter of `S` is itself a sampleable type; return a value of type `S`.
+    Note that tuple types such as `Tuple{Vararg{T}}` (unknown size) and `Tuple{1:2}` (parameterized with a value) are not supported.
 
 
 `S` defaults to [`Float64`](@ref).
diff --git a/stdlib/Random/src/generation.jl b/stdlib/Random/src/generation.jl
index 293ce2f27ce21..1e3edea21c03b 100644
--- a/stdlib/Random/src/generation.jl
+++ b/stdlib/Random/src/generation.jl
@@ -169,13 +169,13 @@ end
 
 ### random tuples
 
-function Sampler(RNG::Type{<:AbstractRNG}, t::Type{T}, n::Repetition) where {T <: Tuple}
-    tail_sp_ = Sampler(RNG, Tuple{Base.tail(fieldtypes(t))...}, n)
-    SamplerTag{t}((Sampler(RNG, fieldtype(t, 1), n), tail_sp_.data...))
+function Sampler(::Type{RNG}, ::Type{T}, n::Repetition) where {T<:Tuple, RNG<:AbstractRNG}
+    tail_sp_ = Sampler(RNG, Tuple{Base.tail(fieldtypes(T))...}, n)
+    SamplerTag{T}((Sampler(RNG, fieldtype(T, 1), n), tail_sp_.data...))
 end
 
-function Sampler(RNG::Type{<:AbstractRNG}, t::Type{Tuple{Vararg{T, N}}}, n::Repetition) where {T, N}
-    SamplerTag{t}((Sampler(RNG, T, n),))
+function Sampler(::Type{RNG}, ::Type{Tuple{Vararg{T, N}}}, n::Repetition) where {T, N, RNG<:AbstractRNG}
+    SamplerTag{Tuple{Vararg{T, N}}}((Sampler(RNG, T, n),))
 end
 
 function rand(rng::AbstractRNG, sp::SamplerTag{T}) where T<:Tuple
diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index 9ef690e3078ef..07ad0b1ff3726 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -446,6 +446,10 @@ for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
         @test_throws MethodError r(rng..., Number, (2,3))
         @test_throws MethodError r(rng..., Any, 1)
     end
+
+    # Test that you cannot call rand with a tuple type of unknown size or with isbits parameters
+    @test_throws ArgumentError rand(rng..., Tuple{Vararg{Int}})
+    @test_throws TypeError rand(rng..., Tuple{1:2})
 end
 
 function hist(X, n)

From a19e2ca62c1c5bdc004bc3c2f8f9325339ea562a Mon Sep 17 00:00:00 2001
From: adienes <51664769+adienes@users.noreply.github.com>
Date: Fri, 15 Sep 2023 10:50:26 -0400
Subject: [PATCH 13/15] Update Random.jl complex domain docstring

---
 stdlib/Random/src/Random.jl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index e5e2b4251bde6..1fd45e675c6fe 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -325,7 +325,8 @@ Pick a random element or array of random elements from the set of values specifi
 
   + concrete floating point types sample from `[0, 1)`
 
-  + concrete complex types `Complex{T}` sample from `rand(T) + rand(T) * im`
+  + concrete complex types `<:Complex{T}` if `T` is a sampleable type take their real and imaginary components
+    independently from the set of values corresponding to `T`, but are not supported if `T` is not sampleable.
 
   + all `<:AbstractChar` types sample from the set of valid Unicode scalars
 

From e89dd567982b7cf677775521a9f65d74a145c705 Mon Sep 17 00:00:00 2001
From: adienes <51664769+adienes@users.noreply.github.com>
Date: Fri, 15 Sep 2023 10:52:13 -0400
Subject: [PATCH 14/15] Update Random.jl complex docstring

---
 stdlib/Random/src/Random.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/Random/src/Random.jl b/stdlib/Random/src/Random.jl
index 1fd45e675c6fe..54cae3adbf953 100644
--- a/stdlib/Random/src/Random.jl
+++ b/stdlib/Random/src/Random.jl
@@ -325,7 +325,7 @@ Pick a random element or array of random elements from the set of values specifi
 
   + concrete floating point types sample from `[0, 1)`
 
-  + concrete complex types `<:Complex{T}` if `T` is a sampleable type take their real and imaginary components
+  + concrete complex types `Complex{T}` if `T` is a sampleable type take their real and imaginary components
     independently from the set of values corresponding to `T`, but are not supported if `T` is not sampleable.
 
   + all `<:AbstractChar` types sample from the set of valid Unicode scalars

From 6a192adfbacb99facdf126980aee94d75c9655d5 Mon Sep 17 00:00:00 2001
From: Rafael Fourquet <fourquet.rafael@gmail.com>
Date: Fri, 29 Sep 2023 12:05:33 +0200
Subject: [PATCH 15/15] fix test caused by merge with master

---
 stdlib/Random/test/runtests.jl | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/stdlib/Random/test/runtests.jl b/stdlib/Random/test/runtests.jl
index 0d479cbe051f5..3c760441d3746 100644
--- a/stdlib/Random/test/runtests.jl
+++ b/stdlib/Random/test/runtests.jl
@@ -323,7 +323,9 @@ for rng in ([], [MersenneTwister(0)], [RandomDevice()], [Xoshiro()])
             a2 = f(rng..., T, 2, 3)   ::Array{T, 2}
             a3 = f(rng..., T, b2, u3) ::Array{T, 2}
             a4 = f(rng..., T, (2, 3)) ::Array{T, 2}
-            @test size(a0) == ()
+            if T <: Number
+                @test size(a0) == ()
+            end
             @test size(a1) == (5,)
             @test size(a2) == size(a3) == size(a4) == (2, 3)
             if T <: AbstractFloat && f === rand