Package section is responsible for splitting a program into its different sections without attempting to parse the contents.

Parse parses a Program.

Change is a single change in a patch.

Meta represents the metavariables section of a change.

Patch is the patch portion of the change containing the unified diff of the match/transformation.

Program is a single gopatch program consisting of one or more changes.

VarDecl is a single var declaration in a metavariable block.