====================================
Variable definition
====================================
{{ $variable := pipeline }}
---
(source_file
    (template
        (variable_definition
            (variable (identifier))
            (function_call (identifier)))))

====================================
Variable assignment
====================================
{{ $variable = pipeline }}
---
(source_file
    (template
        (assignment
            (variable (identifier))
            (function_call (identifier)))))

====================================
Range pipeline assignment
====================================
{{ range $index, $element := pipeline }}{{ $index }}{{ $element }}{{ end }}
---
(source_file
    (template
        (range_action
            (range_variable_definition
                (variable (identifier))
                (variable (identifier))
                (function_call
                    (identifier)))
            (variable (identifier))
            (variable (identifier)))))
