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replace the API of replace
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@rfourquet
rfourquet committed Jan 23, 2018
1 parent 7756d0e commit 0284ab3
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89 changes: 61 additions & 28 deletions base/set.jl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -573,6 +573,8 @@ convert(::Type{T}, s::AbstractSet) where {T<:AbstractSet} = T(s)
For each pair `old=>new` in `old_new`, replace all occurrences
of `old` in collection `A` by `new`.
As a special case, if `new` is `nothing`, then the occurence is deleted;
wrap `nothing` as `Some(nothing)` if `nothing` must be used as the new value.
If `count` is specified, then replace at most `count` occurrences in total.
See also [`replace`](@ref replace(A, old_new::Pair...)).
Expand All @@ -587,17 +589,26 @@ julia> replace!([1, 2, 1, 3], 1=>0, 2=>4, count=2)
julia> replace!(Set([1, 2, 3]), 1=>0)
Set([0, 2, 3])
julia> replace!(Any[1, 2, 3], 1=>nothing, 3=>Some(nothing))
[2, nothing]
```
"""
replace!(A, old_new::Pair...; count::Integer=typemax(Int)) = _replace!(A, eltype(A), count, old_new)

wrap_nothing(x) = x
wrap_nothing(::Nothing) = Some(nothing)
unwrap_nothing(x) = x
unwrap_nothing(::Some{Nothing}) = nothing

# we use this wrapper because using directly eltype(A) as the type
# parameter below for Some degrades performance
function _replace!(A, ::Type{K}, count::Integer, old_new::Tuple{Vararg{Pair}}) where K
@inline function prednew(x)
for o_n in old_new
first(o_n) == x && return Some{K}(last(o_n))
first(o_n) == x && return last(o_n)
end
wrap_nothing(x)
end
replace!(prednew, A, count=count)
end
Expand All @@ -607,6 +618,8 @@ end
Replace all occurrences `x` in collection `A` for which `pred(x)` is true
by `new`.
As a special case, if `new` is `nothing`, then the occurence is deleted;
wrap `nothing` as `Some(nothing)` if `nothing` must be used as the new value.
# Examples
```jldoctest
Expand All @@ -621,27 +634,27 @@ julia> replace!(isodd, A, 0, count=2)
```
"""
replace!(pred::Callable, A, new; count::Integer=typemax(Int)) =
replace!(x -> if pred(x) Some(new) end, A, count=count)
replace!(x -> ifelse(pred(x), new, wrap_nothing(x)), A, count=count)

"""
replace!(prednew::Function, A; [count::Integer])
replace!(new::Function, A; [count::Integer])
For each value `x` in `A`, `prednew(x)` is called and must
return either `nothing`, in which case no replacement occurs,
or a value, possibly wrapped as a [`Some`](@ref) object, which
will be used as a replacement for `x`.
Replace all occurrences `x` in collection `A`
by `new(x)`.
As a special case, if `new(x)` is `nothing`, then the occurence is deleted;
wrap `nothing` as `Some(nothing)` if `nothing` must be used as the new value.
# Examples
```jldoctest
julia> replace!(x -> isodd(x) ? 2x : nothing, [1, 2, 3, 4])
julia> replace!(x -> isodd(x) ? 2x : x, [1, 2, 3, 4])
4-element Array{Int64,1}:
2
2
6
4
julia> replace!(Union{Int,Nothing}[0, 1, 2, nothing, 4], count=2) do x
x !== nothing && iseven(x) ? Some(nothing) : nothing
x !== nothing && iseven(x) ? Some(nothing) : x
end
5-element Array{Union{Nothing,Int64},1}:
nothing
Expand All @@ -651,7 +664,7 @@ julia> replace!(Union{Int,Nothing}[0, 1, 2, nothing, 4], count=2) do x
4
julia> replace!(Dict(1=>2, 3=>4)) do kv
if first(kv) < 3; first(kv)=>3 end
first(kv) < 3 ? first(kv)=>3 : kv
end
Dict{Int64,Int64} with 2 entries:
3 => 4
Expand Down Expand Up @@ -706,7 +719,7 @@ julia> replace(isodd, [1, 2, 3, 1], 0, count=2)
```
"""
replace(pred::Callable, A, new; count::Integer=typemax(Int)) =
replace!(x -> if pred(x) Some(new) end, copy(A), count=count)
replace!(pred, copy(A), new, count=count)

"""
replace(prednew::Function, A; [count::Integer])
Expand Down Expand Up @@ -758,43 +771,63 @@ replace(a::AbstractString, b::Pair, c::Pair) = throw(MethodError(replace, (a, b,
askey(k, ::AbstractDict) = k.first
askey(k, ::AbstractSet) = k

function _replace_update_dict!(repl::Vector{<:Pair}, x, y::Some)
push!(repl, x => y.value)
true
function _replace_update_dict!(repl::Vector{<:Pair}, x, y)
if x === y
false
else
push!(repl, x => y)
true
end
end

_replace_update_dict!(repl::Vector{<:Pair}, x, ::Nothing) = false
_replace_update_dict!(repl::Vector{<:Pair}, x, y) = _replace_update_dict!(repl, x, Some(y))

function _replace!(prednew::Callable, A::Union{AbstractDict,AbstractSet}, count::Int)
repl = Pair{eltype(A),eltype(A)}[]
repl = Pair{eltype(A),eltype(A)}[] # first == second means delete
c = 0
for x in A
c += _replace_update_dict!(repl, x, prednew(x))
y = prednew(x)
if y === nothing
push!(repl, x=>x) # delete
c += 1
else
c += _replace_update_dict!(repl, x, unwrap_nothing(y))
end
c == count && break
end
for oldnew in repl
pop!(A, askey(first(oldnew), A))
end
for oldnew in repl
push!(A, last(oldnew))
first(oldnew) !== last(oldnew) && push!(A, last(oldnew))
end
end

### AbstractArray

function _replace_update!(A::AbstractArray, i::Integer, y::Some)
@inbounds A[i] = y.value
true
function _replace_update!(A::AbstractArray, i::Integer, del::Int, y)
@inbounds begin
rep = A[i] !== y
if rep | (del != 0)
A[i-del] = y
end
return rep
end
end

_replace_update!(A::AbstractArray, i::Integer, ::Nothing) = false
_replace_update!(A::AbstractArray, i::Integer, y) = _replace_update!(A, i, Some(y))

function _replace!(prednew::Callable, A::AbstractArray, count::Int)
c = 0
for i in eachindex(A)
c += _replace_update!(A, i, prednew(A[i]))
del = 0 # number of deleted items
@inbounds for i in eachindex(A)
y = prednew(A[i])
if y === nothing
A::AbstractVector
del += 1
c += 1
else
c += _replace_update!(A, i, del, unwrap_nothing(y))
end
c == count && break
end
if del > 0 # implies A isa AbstractVector
resize!(A, length(A)-del)
end
end
90 changes: 43 additions & 47 deletions test/sets.jl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -492,47 +492,43 @@ end
end

@testset "replace! & replace" begin
maybe1(v, p) = if p Some(v) end
maybe2(v, p) = if p v end

for maybe = (maybe1, maybe2)
a = [1, 2, 3, 1]
@test replace(x->maybe(2x, iseven(x)), a) == [1, 4, 3, 1]
@test replace!(x->maybe(2x, iseven(x)), a) === a
@test a == [1, 4, 3, 1]
@test replace(a, 1=>0) == [0, 4, 3, 0]
for count = (1, 0x1, big(1))
@test replace(a, 1=>0, count=count) == [0, 4, 3, 1]
end
@test replace!(a, 1=>2) === a
@test a == [2, 4, 3, 2]
@test replace!(x->2x, a, count=0x2) == [4, 8, 3, 2]

d = Dict(1=>2, 3=>4)
@test replace(x->x.first > 2, d, 0=>0) == Dict(1=>2, 0=>0)
@test replace!(x->maybe(x.first=>2*x.second, x.first > 2), d) === d
@test d == Dict(1=>2, 3=>8)
@test replace(d, (3=>8)=>(0=>0)) == Dict(1=>2, 0=>0)
@test replace!(d, (3=>8)=>(2=>2)) === d
@test d == Dict(1=>2, 2=>2)
for count = (1, 0x1, big(1))
@test replace(x->x.second == 2, d, 0=>0, count=count) in [Dict(1=>2, 0=>0),
Dict(2=>2, 0=>0)]
end
s = Set([1, 2, 3])
@test replace(x->maybe(2x, x>1), s) == Set([1, 4, 6])
for count = (1, 0x1, big(1))
@test replace(x->maybe(2x, x>1), s, count=count) in [Set([1, 4, 3]), Set([1, 2, 6])]
end
@test replace(s, 1=>4) == Set([2, 3, 4])
@test replace!(s, 1=>2) === s
@test s == Set([2, 3])
@test replace!(x->2x, s, count=0x1) in [Set([4, 3]), Set([2, 6])]
a = [1, 2, 3, 1]
@test replace(x -> iseven(x) ? 2x : x, a) == [1, 4, 3, 1]
@test replace!(x -> iseven(x) ? 2x : x, a) === a
@test a == [1, 4, 3, 1]
@test replace(a, 1=>0) == [0, 4, 3, 0]
for count = (1, 0x1, big(1))
@test replace(a, 1=>0, count=count) == [0, 4, 3, 1]
end
@test replace!(a, 1=>2) === a
@test a == [2, 4, 3, 2]
@test replace!(x->2x, a, count=0x2) == [4, 8, 3, 2]

d = Dict(1=>2, 3=>4)
@test replace(x->x.first > 2, d, 0=>0) == Dict(1=>2, 0=>0)
@test replace!(x -> x.first > 2 ? x.first=>2*x.second : x, d) === d
@test d == Dict(1=>2, 3=>8)
@test replace(d, (3=>8)=>(0=>0)) == Dict(1=>2, 0=>0)
@test replace!(d, (3=>8)=>(2=>2)) === d
@test d == Dict(1=>2, 2=>2)
for count = (1, 0x1, big(1))
@test replace(x->x.second == 2, d, 0=>0, count=count) in [Dict(1=>2, 0=>0),
Dict(2=>2, 0=>0)]
end
s = Set([1, 2, 3])
@test replace(x -> x > 1 ? 2x : x, s) == Set([1, 4, 6])
for count = (1, 0x1, big(1))
@test replace(x -> x > 1 ? 2x : x, s, count=count) in [Set([1, 4, 3]), Set([1, 2, 6])]
end
@test replace(s, 1=>4) == Set([2, 3, 4])
@test replace!(s, 1=>2) === s
@test s == Set([2, 3])
@test replace!(x->2x, s, count=0x1) in [Set([4, 3]), Set([2, 6])]

for count = (0, 0x0, big(0))
@test replace([1, 2], 1=>0, 2=>0, count=count) == [1, 2] # count=0 --> no replacements
end
for count = (0, 0x0, big(0))
@test replace([1, 2], 1=>0, 2=>0, count=count) == [1, 2] # count=0 --> no replacements
end

# test collisions with AbstractSet/AbstractDict
@test replace!(x->2x, Set([3, 6])) == Set([6, 12])
@test replace!(x->2x, Set([1:20;])) == Set([2:2:40;])
Expand All @@ -541,16 +537,16 @@ end
# test Some(nothing)
a = [1, 2, nothing, 4]
@test replace(x -> x === nothing ? 0 : Some(nothing), a) == [nothing, nothing, 0, nothing]
@test replace(x -> x === nothing ? 0 : nothing, a) == [1, 2, 0, 4]
@test replace!(x -> x !== nothing ? Some(nothing) : nothing, a) == [nothing, nothing, nothing, nothing]
@test replace(iseven, Any[1, 2, 3, 4], nothing) == [1, nothing, 3, nothing]
@test replace(Any[1, 2, 3, 4], 1=>nothing, 3=>nothing) == [nothing, 2, nothing, 4]
@test replace(x -> x === nothing ? 0 : x, a) == [1, 2, 0, 4]
@test replace!(x -> x !== nothing ? Some(nothing) : Some(x), a) == [nothing, nothing, nothing, nothing]
@test replace(iseven, Any[1, 2, 3, 4], Some(nothing)) == [1, nothing, 3, nothing]
@test replace(Any[1, 2, 3, 4], 1=>Some(nothing), 3=>Some(nothing)) == [nothing, 2, nothing, 4]
s = Set([1, 2, nothing, 4])
@test replace(x -> x === nothing ? 0 : Some(nothing), s) == Set([0, nothing])
@test replace(x -> x === nothing ? 0 : nothing, s) == Set([1, 2, 0, 4])
@test replace(x -> x !== nothing ? Some(nothing) : nothing, s) == Set([nothing])
@test replace(iseven, Set(Any[1, 2, 3, 4]), nothing) == Set([1, nothing, 3, nothing])
@test replace(Set(Any[1, 2, 3, 4]), 1=>nothing, 3=>nothing) == Set([nothing, 2, nothing, 4])
@test replace(x -> x === nothing ? 0 : x, s) == Set([1, 2, 0, 4])
@test replace(x -> x !== nothing ? Some(nothing) : x, s) == Set([nothing])
@test replace(iseven, Set(Any[1, 2, 3, 4]), Some(nothing)) == Set([1, nothing, 3, nothing])
@test replace(Set(Any[1, 2, 3, 4]), 1=>Some(nothing), 3=>Some(nothing)) == Set([nothing, 2, nothing, 4])

# avoid recursive call issue #25384
@test_throws MethodError replace!("")
Expand Down

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