Internal returns the content of an internal asset registered under the given name, or nil when none was found.

MockInternal mocks the contents of an internal asset for use in testing.

MockSnippetsForEdition mocks the contents of per-edition snippets.

SnippetForEdition returns a snippet registered under given name, applicable for the provided edition number.

ForEditions wraps a snippet that is used in editions starting with FirstEdition.