René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Slow function when parameter is Mandatory its Type is specified","articleBody":"Steps to reproduce\r\n------------------\r\n\r\n```powershell\r\n[Byte[]]$Value = [System.IO.File]::ReadAllBytes('C:\\Some10MBfile')\r\n\r\n#  ~1000ms for 10MB array\r\n#  ~0.5ms for 1byte array\r\nfunction MandType {\r\n    Param (\r\n        [parameter(Mandatory=$True)]\r\n        [Byte[]]$Value\r\n    )\r\n}\r\n\r\n#  ~0.3ms for 10MB array\r\nfunction TypeOnly {\r\n    Param (\r\n        [parameter()]\r\n        [Byte[]]$Value\r\n    )\r\n}\r\n\r\n#  ~0.3 for 10MB array\r\nfunction MandOnly {\r\n    Param (\r\n        [parameter(Mandatory=$True)]\r\n        $Value\r\n    )\r\n}\r\n\r\n(Measure-Command { MandType $Value}).TotalMilliseconds\r\n(Measure-Command { MandType ([Byte[]]@(0))}).TotalMilliseconds\r\n(Measure-Command { TypeOnly $Value}).TotalMilliseconds\r\n(Measure-Command { MandOnly $Value}).TotalMilliseconds\r\n\r\n```\r\n\r\nExpected behavior\r\n-----------------\r\nAll versions of the above functions should behave identically and complete immediately, regardless of of parameter size as the functions perform no functions.\r\n```none\r\n1.1\r\n1.1\r\n1.1\r\n1.1\r\n```\r\n\r\nActual behavior\r\n---------------\r\nWhen setting a parameter to Mandatory, specifying its Type, and passing a large array in, the function will pause for some amount of time before starting.\r\n```none\r\n1000\r\n1.1\r\n1.1\r\n1.1\r\n```\r\n\r\nEnvironment data\r\n----------------\r\n\r\n```powershell\r\nPS C:\\\u003e $PSVersionTable\r\n\r\nName                           Value\r\n----                           -----\r\nPSVersion                      6.0.0-beta.9\r\nPSEdition                      Core\r\nGitCommitId                    v6.0.0-beta.9\r\nOS                             Microsoft Windows 10.0.16299\r\nPlatform                       Win32NT\r\nPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}\r\nPSRemotingProtocolVersion      2.3\r\nSerializationVersion           1.1.0.1\r\nWSManStackVersion              3.0\r\n\r\n\r\nPS C:\\\u003e $PSVersionTable\r\n\r\nName                           Value\r\n----                           -----\r\nPSVersion                      5.1.16299.19\r\nPSEdition                      Desktop\r\nPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}\r\nBuildVersion                   10.0.16299.19\r\nCLRVersion                     4.0.30319.42000\r\nWSManStackVersion              3.0\r\nPSRemotingProtocolVersion      2.3\r\nSerializationVersion           1.1.0.1\r\n```\r\n","author":{"url":"https://github.com/Atamido","@type":"Person","name":"Atamido"},"datePublished":"2017-11-10T23:46:51.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/5417/PowerShell/issues/5417"}