Struct ExprArg 

pub struct ExprArg {
    pub position: usize,
    pub nesting: usize,
}

A positional argument placeholder.

Represents a reference to an input value by position. During substitution, arg(n) is replaced with the nth value from the input.

Examples

arg(0)  // refers to the first input value
arg(1)  // refers to the second input value

Fields

position: usize

The zero-based position of the argument.

nesting: usize

Which “argument scope” this references. This is the number of scopes up from the current scope. Scopes are created by functional expressions like Expr::Map.

Implementations

impl ExprArg

pub fn new(position: usize) -> ExprArg

Trait Implementations

impl Clone for ExprArg

fn clone(&self) -> ExprArg

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExprArg

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

Formats the value using the given formatter.

impl From<ExprArg> for Expr

fn from(value: ExprArg) -> Self

Converts to this type from the input type.

impl From<ExprArg> for Source

fn from(value: ExprArg) -> Self

Converts to this type from the input type.

impl From<ExprArg> for SourceTable

fn from(value: ExprArg) -> Self

Converts to this type from the input type.

impl From<ExprArg> for TableRef

fn from(value: ExprArg) -> Self

Converts to this type from the input type.

impl From<usize> for ExprArg

fn from(value: usize) -> Self

Converts to this type from the input type.

impl Hash for ExprArg

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ExprArg

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ExprArg

impl Eq for ExprArg

impl StructuralPartialEq for ExprArg