Struct Reader 

pub struct Reader { /* private fields */ }

A CSV file, positioned at a record boundary.

Implementations

impl Reader

pub fn open(file: Box<dyn File>, path: &str) -> Result<Self>

Opens a file, works out how it is written, and positions it at the first row.

The path is kept because the error a bad value produces names it, the way DuckDB’s does.

Errors

When the file cannot be read, and when the first block of it does not hold one whole record, which is a single line longer than a megabyte and is not a CSV file anybody meant to write.

pub fn fields(&self) -> Vec<Field>

The columns this reader will produce, in order.

pub fn project(&mut self, columns: &[usize]) -> Result<()>

Reads only these columns, by position in the file, in this order.

Errors

When a position is past the end of the file’s columns.

pub const fn dialect(&self) -> Dialect

How this file is punctuated, which is what the sniffer decided.

pub fn next_chunk(&mut self) -> Result<Option<Chunk>>

The next chunk, or None at the end of the file.

Errors

A read error, a malformed record, or a value that does not fit the type the sample chose for its column.

Trait Implementations

impl Debug for Reader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.