Struct csvsc::Headers

pub struct Headers { /* fields omitted */ }

A structure for keeping relationship between the headers and their positions

Implementations

impl Headers

pub fn from_row(row: Row) -> Headers

pub fn get_field<'r>(&self, row: &'r Row, field: &str) -> Option<&'r str>

Retrieves a field from a row given it's header name

use csvsc::{Headers, Row};

let headers = Headers::from_row(Row::from(vec!["id", "val"]));
let row = Row::from(vec!["1", "40"]);

assert_eq!(headers.get_field(&row, "id"), Some("1"));
assert_eq!(headers.get_field(&row, "val"), Some("40"));
assert_eq!(headers.get_field(&row, "foo"), None);

pub fn hash(&self, row: &Row, columns: &[String]) -> Result<u64, String>

Creates a hash for the row given as first argument only considering the columns specified by the second argument.

use csvsc::{Headers, Row};

let headers = Headers::from_row(Row::from(vec!["id", "name", "val"]));
let row = Row::from(vec!["1", "juan", "40"]);

dbg!(headers.hash(&row, &["id".to_string(), "name".to_string()]));

If no columns are specified, a random hash is chosen. If a column is not found its name is returned as String wrapped in the Err variant of the return value

pub fn add(&mut self, colname: &str) -> Result<(), ()>

Adds a new header. It'll fail if the header is already present

use csvsc::{Headers, Row};

let mut h = Headers::from_row(Row::from(vec!["name"]));

h.add("value").unwrap();

assert_eq!(h, Headers::from_row(Row::from(vec!["name", "value"])));

assert_eq!(h.add("name"), Err(()));
assert_eq!(h, Headers::from_row(Row::from(vec!["name", "value"])));

pub fn len(&self) -> usize

pub fn as_row(&self) -> &Row

pub fn index(&self, field: &str) -> Option<usize>

Obtains the index of the given field in the headers

pub fn contains_key(&self, field: &str) -> bool

pub fn iter(&self) -> StringRecordIter

Trait Implementations

impl Clone for Headers

fn clone(&self) -> Headers

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Headers

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

Formats the value using the given formatter.

impl PartialEq<Headers> for Headers

fn eq(&self, other: &Headers) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Headers) -> bool

This method tests for !=.

impl PartialEq<Headers> for Row

fn eq(&self, other: &Headers) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl StructuralPartialEq for Headers