Struct Sampled 

pub struct Sampled {
    pub columns: Vec<String>,
    pub nests: Option<bool>,
    pub columns_differ: bool,
    pub types_differ: bool,
    pub read: usize,
    pub headerless: bool,
}

What a spread of a directory’s files says about whether they are one table.

One sampling, read once, answering both questions asked of it: whether the files nest, which decides what Enter does, and whether they agree, which decides what the dataset says about itself. Taking them separately meant reading the same three files twice and, worse, letting the two answers disagree.

Fields

columns: Vec<String>

Every column name any sampled file has, first seen first. Empty when nothing could be read.

nests: Option<bool>

Whether every sampled file’s columns are within the widest one’s. None where fewer than two files could be read, which decides nothing.

columns_differ: bool

Whether a column one file has is missing from another. The table is then their union, and a row from a file without the column reads null.

types_differ: bool

Whether a column they share is held in two different types. The half a name test cannot see: amount is an Int64 in one file and a String in the next because one row said N/A, and the read widens it to String for the whole directory without a word unless this says so.

read: usize

How many files were actually read, so a caller can say whether a count over them is exact or a floor.

headerless: bool

Whether the files appear to have no header row, so what came back as names is each file’s first row of data.

datui reads a CSV as having a header, so such a directory cannot be read as one table at all without --no-header: every file contributes its own first row as column names and the union is a wide sheet of nulls. Neither a nesting verdict nor a note about columns means anything here — this is the thing to say instead.

Implementations

impl Sampled

pub fn disagreement(&self) -> Disagreement

How the files differ, for the note that says so.

Trait Implementations

impl Clone for Sampled

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Sampled

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

Formats the value using the given formatter.

impl Default for Sampled

fn default() -> Self

Returns the “default value” for a type.