Function parse_path 

pub(crate) fn parse_path(
    s: &str,
) -> Result<Vec<VariantPathElement<'_>>, ArrowError>

Parse a path string into a vector of VariantPathElement.

Syntax

• .field or field - access object field (do not support special char)
• [index] - access array element by index
• [field] - access object field (support special char with escape \)

Escape Rules

Inside brackets [...]:

• \\ -> literal \
• \] -> literal ]
• Any other \x -> literal x

Outside brackets, no escaping is supported.

Examples

• "" -> empty path
• "foo" -> single field foo
• "foo.bar" -> nested fields foo, bar
• "[1]" -> array index 1
• "foo[1].bar" -> field foo, index 1, field bar
• "[a.b]" -> field a.b (dot is literal inside bracket)
• "[a\\]b]" -> field a]b (escaped ]
• etc.

Errors

• Leading . (e.g., ".foo")
• Trailing . (e.g., "foo.")
• Unclosed ‘[’ (e.g., "foo[1")
• Unexpected ‘]’ (e.g., "foo]")
• Trailing ‘`’ inside bracket (treated as unclosed bracket)