Function output

The example function included in Chapter 1, PowerShell Primer, used string substitution and returned the single result of that operation. As a reminder, here it is again:

function Get-PowerShellVersionMessage{
param($name)
    $PowerShellVersion=$PSVersionTable.PSVersion
    return "We're using $PowerShellVersion, $name!"
}

This pattern (that is, performing a calculation and returning the result) is common to procedural programming languages such as C#, Java, and Visual Basic. In PowerShell, however, functions are more complicated than the usage in this scenario in several ways.

In statically-typed languages, the type of a function (that is, the type of a value returned by the function) is either declared as part of the function definition or inferred by the compiler. In PowerShell, the only consideration of a type associated with the output of a function is in the help provided for the function. This output type can be used by a PowerShell host to guide IntelliSense...