Сумма числовых переменных среды Windows

gci env:* | sort-object name

$ErrorActionPreference='SilentlyContinue'
((((Get-ChildItem env:*).Value).ForEach{[int]$_}) | Measure-Object -Sum).Sum

[Linq.Enumerable]::Sum([Double[]](Get-ChildItem env:).Value.Where{$_ -as [Double]})

((Get-ChildItem env:*).Value.Where{$_ -match '^\d+$'} | Measure-Object -Sum).Sum

time {
  ((Get-ChildItem env:*).Value.Where{$_ -match '^\d+$'} | Measure-Object -Sum).Sum
}, {
  [Linq.ParallelEnumerable]::Sum([Linq.ParallelEnumerable]::AsParallel([Int32[]](Get-ChildItem env:).Value.Where{$_ -match '^\d'}))
}, {
  ((Get-ChildItem env:).Value.Where{$_ -match '^\d'} | Measure-Object -Sum).Sum
}-Count 1000

Total ms: 17461.1072
Total ms: 7797.5296
Total ms: 8391.3663

E:\sandbox
[56] λ $env:dec = 10
 
E:\sandbox
[57] λ (Get-ChildItem env:).Value.Where{$_ -match '^\d'}
10
3,14159265358979
...
 
E:\sandbox
[58] λ Get-ChildItem env:dec
 
Name                           Value
----                           -----
dec                            10

$env:hyb = '2str'

PowerShell 7.0.0-preview.1
Copyright (c) Microsoft Corporation. All rights reserved.
 
https://aka.ms/pscore6-docs
Type 'help' to get help.
 
PS C:\> [sum](1,2,3)
Unable to find type [sum].
At line:1 char:2
+ [sum](1,2,3)
+  ~~~
+ CategoryInfo          : InvalidOperation: (sum:TypeName) [], RuntimeException
+ FullyQualifiedErrorId : TypeNotFound
 
PS ***$PSVersionTable
 
Name                           Value
----                           -----
PSVersion                      7.0.0-preview.1
PSEdition                      Core
GitCommitId                    7.0.0-preview.1
OS                             Microsoft Windows 10.0.15063
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

$env:i = 10
(ls env:i).value.gettype().name

iex((ls env:).value -match '^\p{N}+$' -join '+')