Adding Aliases Transpiler (#106)

Author: James Brundage

Transpilers/Parameters/Aliases.psx.ps1

@@ -0,0 +1,79 @@
+<#
+.SYNOPSIS
+    Dynamically Defines Aliases
+.DESCRIPTION
+    Can Dynamically Define Aliases.
+
+    When uses in a parameter attribute, -Aliases will define a list of aliases.
+
+    When used with a variable, [Aliases] will Set-Alias on each value in the variable.
+.EXAMPLE
+    {
+        $aliases = "Foo", "Bar", "Baz"
+        [Aliases(Command="Get-Process")]$aliases
+    } | .>PipeScript
+.Example
+    {
+        param(
+        [Aliases(Aliases={
+           ([char]'a'..[char]'z')
+        })]
+        [string]
+        $Drive
+        )
+    } | .>PipeScript
+#>
+[CmdletBinding(DefaultParameterSetName='AliasNames')]
+[Alias('SmartAlias','DynamicAlais')]
+param(
+# A list of aliases
+[Parameter(Mandatory,ParameterSetName='AliasNames')]
+[Alias('Alias')]
+[string[]]
+$Aliases,
+
+# If provided, will prefix each alias
+[string]
+$Prefix,
+
+# If provided, will add a suffix to each alias
+[string]
+$Suffix,
+
+# The command being aliased.  This is only required when transpiling a variable.
+[Parameter(Mandatory,ParameterSetName='VariableExpressionAST')]
+[string]
+$Command,
+
+[Parameter(ParameterSetName='VariableExpressionAST')]
+[switch]
+$PassThru,
+
+# A VariableExpression.  
+# If provided, this will be treated as the alias name or list of alias names.
+[Parameter(Mandatory,ValueFromPipeline,ParameterSetName='VariableExpressionAST')]
+[Management.Automation.Language.VariableExpressionAST]
+$VariableAST
+)
+
+process {
+    if ($PSCmdlet.ParameterSetName -eq 'VariableExpressionAST') {
+[ScriptBlock]::Create($({
+@(foreach ($alias in @($aliasNames)) {
+    Set-Alias "${Prefix}$alias${Suffix}" "$Command" -PassThru:$PassThru
+})
+} -replace '\${Prefix}', $Prefix -replace 
+    '\${Suffix}', $Suffix -replace 
+    '\$Command', $Command -replace 
+    '\$AliasNames', "$variableAst" -replace
+    '\$PassThru', ('$' + ($PassThru -as [bool]))
+))
+    } else {
+        $aliasValues = 
+            @(foreach ($alias in $aliasNames) {
+                "$(if ($Prefix) { $Prefix })$alias$(if ($Suffix) { $Suffix })"            
+            })
+[scriptblock]::Create("[Alias('$($Aliases -join "','")')]param()")
+    }
+}
+