Pkg/csv/Reader

Reader

type Reader = Reader

A CSV reader.

RFC 4180

Methods

new

pub fn new(reader: Read, delimiter: char = ',', comment: char? = nil, has_headers: bool = true): Reader

[src]

pub fn new(
    reader: Read, delimiter: char = ',', comment: char? = nil, has_headers: bool = true
): Reader {
    return _csv.Reader.new(_create_native_read(reader), delimiter, comment, has_headers) as Reader;
}

Creates a new CSV reader from a std.io.Read.

Creates a new CSV reader from a std.io.Read.

Options

• delimiter - A char that separates fields in a record, default: ,.
• comment - A char that starts a comment, default: nil.
• has_headers - Whether to treat the first row as a special header row, default: true.

The reader is a streaming CSV parser.

headers

pub fn headers(self): Record throws CsvError, IoError, Utf8Error

[src]

pub fn headers(self): Record throws CsvError, IoError, Utf8Error {
    let record = try (self as _csv.Reader).headers();
    return record as Record;
}

Returns the first record as headers.

Returns the first record as headers.

• If no record has been read yet, then this will force parsing of the first record.
• If there was a problem parsing the record or if it wasn't valid UTF-8, then this returns an error.
• If the underlying reader emits EOF before any data, then this returns an empty record.

Example

use csv.Reader;
use std.io.{Read, Cursor};

let cursor = Cursor.new("hello,100".bytes());
let reader = Reader.new(cursor);
let record = try! reader.headers();

next

pub fn next(self): Record? throws CsvError, IoError, Utf8Error

[src]

pub fn next(self): Record? throws CsvError, IoError, Utf8Error {
    if (let record = try (self as _csv.Reader).next()) {
        return record as Record;
    } else {
        return nil;
    }
}

Returns the next record.

Returns the next record.

• If the record is invalid UTF-8, then this returns an error.
• If the underlying reader emits EOF, then this returns nil.

Example

use csv.Reader;
use std.io.{Read, Cursor};

let cursor = Cursor.new("hello,100".bytes());
let record = try! Reader.new(cursor).next();

scan

pub fn scan<T>(self): T? throws CsvError, IoError, Utf8Error

[src]

pub fn scan<T>(self): T? throws CsvError, IoError, Utf8Error {
    return try (self as _csv.Reader).scan::<T>();
}

Get the next record and deserialize it.

Get the next record and deserialize it.

Example

use std.io.Cursor;
use csv.Reader;

struct Record {
    name: string,
    value: int,
}

let csv = `
name,value
a,10
b,20
c,30
`;

fn main() throws {
    let reader = Reader.new(Cursor.new(csv));
    assert_eq try reader.scan::<Record>(), Record { name: "a", value: 10 };
    assert_eq try reader.scan::<Record>(), Record { name: "b", value: 20 };
    assert_eq try reader.scan::<Record>(), Record { name: "c", value: 30 };
}

position

pub fn position(self): Position

[src]

pub fn position(self): Position {
    return (self as _csv.Reader).position;
}

Returns the current position in the CSV.

Returns the current position in the CSV.

Example

use std.io.{Cursor, Read};
use csv.Reader;

let csv = `name,value
a,10
b,20
c,30`;

fn main() throws {
    let cursor = Cursor.new(csv);
    let reader = Reader.new(cursor, has_headers: false);
    assert_eq reader.position().line, 1;
    assert_eq reader.position().byte, 0;

    let record = try reader.next();
    assert_eq reader.position().line, 2;
    assert_eq reader.position().byte, 11;

    let record = try reader.next();
    assert_eq reader.position().line, 3;
    assert_eq reader.position().byte, 16;

    let record = try reader.next();
    assert_eq reader.position().line, 4;
    assert_eq reader.position().byte, 21;
}