export IdSet and document it (#53262)

It feels kind of odd to have `IdDict` exported and documented and not
`IdSet`.

NEWS.md

@@ -87,6 +87,7 @@ New library functions
 * `Sys.username()` can be used to return the current user's username ([#51897]).
 * `wrap(Array, m::Union{MemoryRef{T}, Memory{T}}, dims)` is the safe counterpart to `unsafe_wrap` ([#52049]).
 * `GC.logging_enabled()` can be used to test whether GC logging has been enabled via `GC.enable_logging` ([#51647]).
+* `IdSet` is now exported from Base and considered public ([#53262]).
 
 New library features
 --------------------

base/exports.jl

@@ -65,6 +65,7 @@ export
     Missing,
     NTuple,
     IdDict,
+    IdSet,
     OrdinalRange,
     Pair,
     PartialQuickSort,

base/iddict.jl

@@ -4,11 +4,12 @@
     IdDict([itr])
 
 `IdDict{K,V}()` constructs a hash table using [`objectid`](@ref) as hash and
-`===` as equality with keys of type `K` and values of type `V`.
+`===` as equality with keys of type `K` and values of type `V`. See [`Dict`](@ref)
+for further help and [`IdSet`](@ref) for the set version of this.
 
-See [`Dict`](@ref) for further help. In the example below, The `Dict`
-keys are all `isequal` and therefore get hashed the same, so they get overwritten.
-The `IdDict` hashes by object-id, and thus preserves the 3 different keys.
+In the example below, the `Dict` keys are all `isequal` and therefore get hashed
+the same, so they get overwritten. The `IdDict` hashes by object-id, and thus
+preserves the 3 different keys.
 
 # Examples
 ```julia-repl

base/idset.jl

@@ -1,5 +1,28 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
+"""
+    IdSet{T}([itr])
+    IdSet()
+
+IdSet{T}() constructs a set (see [`Set`](@ref)) using
+`===` as equality with values of type `V`.
+
+In the example below, the values are all `isequal` so they get overwritten.
+The `IdSet` compares by `===` so preserves the 3 different keys.
+
+Examples
+≡≡≡≡≡≡≡≡
+
+julia> Set(Any[true, 1, 1.0])
+Set{Any} with 1 element:
+  1.0
+
+julia> IdSet{Any}(Any[true, 1, 1.0])
+IdSet{Any} with 3 elements:
+  1.0
+  1
+  true
+"""
 mutable struct IdSet{K} <: AbstractSet{K}
     list::Memory{Any}
     idxs::Union{Memory{UInt8}, Memory{UInt16}, Memory{UInt32}}

doc/src/base/collections.md

@@ -225,14 +225,15 @@ Base.valtype
 
 Fully implemented by:
 
-  * [`IdDict`](@ref)
   * [`Dict`](@ref)
+  * [`IdDict`](@ref)
   * [`WeakKeyDict`](@ref)
 
 Partially implemented by:
 
-  * [`BitSet`](@ref)
   * [`Set`](@ref)
+  * [`BitSet`](@ref)
+  * [`IdSet`](@ref)
   * [`EnvDict`](@ref Base.EnvDict)
   * [`Array`](@ref)
   * [`BitArray`](@ref)
@@ -246,6 +247,7 @@ Partially implemented by:
 Base.AbstractSet
 Base.Set
 Base.BitSet
+Base.IdSet
 Base.union
 Base.union!
 Base.intersect
@@ -264,8 +266,10 @@ Base.isdisjoint
 
 Fully implemented by:
 
-  * [`BitSet`](@ref)
   * [`Set`](@ref)
+  * [`BitSet`](@ref)
+  * [`IdSet`](@ref)
+
 
 Partially implemented by:
 

stdlib/TOML/src/TOML.jl

@@ -110,7 +110,7 @@ const ParserError = Internals.ParserError
 
 
 """
-    print([to_toml::Function], io::IO [=stdout], data::AbstractDict; sorted=false, by=identity, inline_tables::Base.IdSet{<:AbstractDict})
+    print([to_toml::Function], io::IO [=stdout], data::AbstractDict; sorted=false, by=identity, inline_tables::IdSet{<:AbstractDict})
 
 Write `data` as TOML syntax to the stream `io`. If the keyword argument `sorted` is set to `true`,
 sort tables according to the function given by the keyword argument `by`. If the keyword argument

stdlib/TOML/src/print.jl

@@ -146,7 +146,7 @@ function print_table(f::MbyFunc, io::IO, a::AbstractDict,
     indent::Int = 0,
     first_block::Bool = true,
     sorted::Bool = false,
-    inline_tables::Base.IdSet,
+    inline_tables::IdSet,
     by::Function = identity,
 )
 
@@ -223,7 +223,7 @@ end
 # API #
 #######
 
-print(f::MbyFunc, io::IO, a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::Base.IdSet{<:AbstractDict}=Base.IdSet{Dict{String}}()) = print_table(f, io, a; sorted, by, inline_tables)
-print(f::MbyFunc,         a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::Base.IdSet{<:AbstractDict}=Base.IdSet{Dict{String}}()) = print(f, stdout, a; sorted, by, inline_tables)
-print(io::IO, a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::Base.IdSet{<:AbstractDict}=Base.IdSet{Dict{String}}()) = print_table(nothing, io, a; sorted, by, inline_tables)
-print(        a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::Base.IdSet{<:AbstractDict}=Base.IdSet{Dict{String}}()) = print(nothing, stdout, a; sorted, by, inline_tables)
+print(f::MbyFunc, io::IO, a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::IdSet{<:AbstractDict}=IdSet{Dict{String}}()) = print_table(f, io, a; sorted, by, inline_tables)
+print(f::MbyFunc,         a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::IdSet{<:AbstractDict}=IdSet{Dict{String}}()) = print(f, stdout, a; sorted, by, inline_tables)
+print(io::IO, a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::IdSet{<:AbstractDict}=IdSet{Dict{String}}()) = print_table(nothing, io, a; sorted, by, inline_tables)
+print(        a::AbstractDict; sorted::Bool=false, by=identity, inline_tables::IdSet{<:AbstractDict}=IdSet{Dict{String}}()) = print(nothing, stdout, a; sorted, by, inline_tables)

stdlib/TOML/test/print.jl

@@ -148,7 +148,7 @@ d = Dict(
     "y" => inline_dict,
     "z" => [1,2,3],
 )
-inline_tables = Base.IdSet{Dict}()
+inline_tables = IdSet{Dict}()
 push!(inline_tables, inline_dict)
 @test toml_str(d; sorted=true, inline_tables) ==
 """
@@ -165,7 +165,7 @@ d = Dict("deps" => Dict(
         "LocalPkg" => Dict("path" => "LocalPkg"),
         "Example" => Dict("url" => "https://github.com/JuliaLang/Example.jl")))
 
-inline_tables = Base.IdSet{Dict}()
+inline_tables = IdSet{Dict}()
 push!(inline_tables, d["sources"]["LocalPkg"])
 push!(inline_tables, d["sources"]["Example"])
 
@@ -180,7 +180,7 @@ Example = {url = "https://github.com/JuliaLang/Example.jl"}
 LocalPkg = {path = "LocalPkg"}
 """
 
-inline_tables = Base.IdSet{Dict}()
+inline_tables = IdSet{Dict}()
 push!(inline_tables, d["sources"]["LocalPkg"])
 s = """
 [deps]

test/sets.jl

@@ -899,8 +899,8 @@ end
     b = [2, 3, 1, 3]
     ua = unique(a)
     ub = unique(b)
-    for TA in (Tuple, identity, Set, BitSet, Base.IdSet{Int}),
-        TB in (Tuple, identity, Set, BitSet, Base.IdSet{Int}),
+    for TA in (Tuple, identity, Set, BitSet, IdSet{Int}),
+        TB in (Tuple, identity, Set, BitSet, IdSet{Int}),
         uA = false:true,
         uB = false:true
         A = TA(uA ? ua : a)
@@ -921,7 +921,7 @@ end
         @test !issetequal(B, A)
         @test !issetequal(B)(A)
         @test !issetequal(A)(B)
-        for T = (Tuple, identity, Set, BitSet, Base.IdSet{Int})
+        for T = (Tuple, identity, Set, BitSet, IdSet{Int})
             @test issetequal(A, T(A))
             @test issetequal(B, T(B))
         end
@@ -982,7 +982,7 @@ end
     c = [3]
     d = [4]
     e = [5]
-    A = Base.IdSet{Vector{Int}}([a, b, c, d])
+    A = IdSet{Vector{Int}}([a, b, c, d])
     @test !isempty(A)
     B = copy(A)
     @test A ⊆ B