Static analysis

Static analysis is the process of evaluating code without executing it. Static analysis in PowerShell makes use of an Abstract Syntax Tree (AST): a tree-like representation of a block of code.

Abstract syntax tree

The AST in PowerShell is available for any script block, for example:

{ Write-Host 'content' }.Ast

The script block that defines a function can be retrieved via Get-Command:

function Write-Content { Write-Host 'content' } 
(Get-Command Write-Content).ScriptBlock

Or the script block defining a function can be retrieved using Get-Item:

function Write-Content { Write-Host 'content' } 
(Get-Item function:\Write-Content).ScriptBlock

It is possible to work down through the content of the script block using AST. For example, the first argument for the command Write-Host might be accessed:

{ Write-Host 'content' }.Ast. 
                         Endblock. 
                         Statements. 
                         PipelineElements. 
                         CommandElements[1...