Function sections 

pub(crate) fn sections(input: &mut &str) -> ModalResult<Vec<Section>>

Parses all %SECTION% blocks from the given input into a list of Sections.

This is the top-level parser used by the higher-level file constructors.

Errors

Returns an error if:

• any section header is missing or malformed,
• a section value list fails to parse,
• or the overall structure of the file is inconsistent.