Function extract_right_operand

nodedb-sql/src/parser/preprocess/vector_ops.rs:51–84

Extract the right operand after `<->`: ARRAY[...], $param, or identifier. Returns (operand_text, consumed_length).

(after: &str)

/// Extract the right operand after `<->`: ARRAY[...], $param, or identifier.
/// Returns (operand_text, consumed_length).
fn extract_right_operand(after: &str) -> Option<(String, usize)> {
    let trimmed = after.trim_start();
    let upper = trimmed.to_uppercase();

    if upper.starts_with("ARRAY[") {
        let mut depth = 0;
        for (i, c) in trimmed.char_indices() {
            match c {
                '[' => depth += 1,
                ']' => {
                    depth -= 1;
                    if depth == 0 {
                        return Some((trimmed[..=i].to_string(), i + 1));
                    }
                }
                _ => {}
            }
        }
        None
    } else if trimmed.starts_with('$') {
        let end = trimmed
            .find(|c: char| !c.is_ascii_alphanumeric() && c != '_' && c != '$')
            .unwrap_or(trimmed.len());
        Some((trimmed[..end].to_string(), end))
    } else {
        let end = trimmed
            .find(|c: char| !c.is_ascii_alphanumeric() && c != '_' && c != '.')
            .unwrap_or(trimmed.len());
        if end == 0 {
            return None;
        }
        Some((trimmed[..end].to_string(), end))
    }
}

/// Rewrite all occurrences of `expr <=> expr` to `vector_cosine_distance(expr, expr)`.
///