<# .SYNOPSIS Checks whether a command with the specified name exists. .PARAMETER Name The name of the command to check. #> function Test-Command { param ( [string] $Name ) [bool] (Get-Command $Name -ErrorAction SilentlyContinue); } <# .SYNOPSIS Checks whether a package with the specified name is installed. .PARAMETER Name The name of the package to check. #> function Test-PSPackage { param( [string] $Name ) [bool] (Get-Package $Name -ErrorAction SilentlyContinue); } <# .SYNOPSIS Checks whether a module with the specified name is installed. .PARAMETER Name The name of the module to check. #> function Test-PSModule { param( [string] $Name ) [bool](Get-Module -ListAvailable $Name -ErrorAction SilentlyContinue); }