Inline.R.psx.ps1

<#
.SYNOPSIS
    R PipeScript Transpiler.
.DESCRIPTION
    Transpiles R with Inline PipeScript into R.

    Because R Scripts only allow single-line comments, this is done using a pair of comment markers.

    # { or # PipeScript{  begins a PipeScript block

    # } or # }PipeScript  ends a PipeScript block

    ~~~r    
    # {

    Uncommented lines between these two points will be ignored

    #  # Commented lines will become PipeScript / PowerShell.
    # param($message = "hello world")
    # "puts `"$message`""

    # }
    ~~~
.EXAMPLE
    Invoke-PipeScript {
        $rScript = '    
    # {

    Uncommented lines between these two points will be ignored

    #  # Commented lines will become PipeScript / PowerShell.
    # param($message = "hello world")
    # "print(`"$message`")"

    # }
    '
    
        [OutputFile('.\HelloWorld.ps1.r')]$rScript
    }

    Invoke-PipeScript .\HelloWorld.ps1.r
#>
[ValidatePattern('\.r$')]
param(
# The command information.  This will include the path to the file.
[Parameter(Mandatory,ValueFromPipeline)]
[Management.Automation.CommandInfo]
$CommandInfo,

# A dictionary of parameters.
[Collections.IDictionary]
$Parameter,

# A list of arguments.
[PSObject[]]
$ArgumentList    
)

begin {
    # We start off by declaring a number of regular expressions:
    $startComment = '(?>\#\s{0,}(?:PipeScript)?\s{0,}\{)'
    $endComment   = '(?>\#\s{0,}\}\s{0,}(?:PipeScript)?\s{0,})'        
    $startRegex = "(?<PSStart>${startComment})"
    $endRegex   = "(?<PSEnd>${endComment})"

    # Create a splat containing arguments to the core inline transpiler
    $Splat      = [Ordered]@{
        StartPattern  = $startRegex
        EndPattern    = $endRegex
         # Using -LinePattern will skip any inline code not starting with #
        LinePattern   = "^\s{0,}\#\s{0,}"
    }
}

process {
    # Add parameters related to the file
    $Splat.SourceFile = $commandInfo.Source -as [IO.FileInfo]
    $Splat.SourceText = [IO.File]::ReadAllText($commandInfo.Source)
    if ($Parameter) { $splat.Parameter = $Parameter }
    if ($ArgumentList) { $splat.ArgumentList = $ArgumentList }

    # Call the core inline transpiler.
    .>PipeScript.Inline @Splat
}