Struct LengthConstraint 

pub struct LengthConstraint { /* private fields */ }

A unified constraint that checks string length properties of a column.

This constraint replaces the individual length constraints and provides a consistent interface for all length-related checks.

Examples

use term_guard::constraints::{LengthConstraint, LengthAssertion};
use term_guard::core::Constraint;

// Check minimum length
let min_constraint = LengthConstraint::new("password", LengthAssertion::Min(8));

// Check maximum length  
let max_constraint = LengthConstraint::new("username", LengthAssertion::Max(20));

// Check length is between bounds
let between_constraint = LengthConstraint::new("description", LengthAssertion::Between(10, 500));

// Check exact length
let exact_constraint = LengthConstraint::new("code", LengthAssertion::Exactly(6));

// Check not empty
let not_empty_constraint = LengthConstraint::new("name", LengthAssertion::NotEmpty);

Implementations

impl LengthConstraint

pub fn new(column: impl Into<String>, assertion: LengthAssertion) -> Self

Creates a new length constraint.

Arguments

• column - The column to check
• assertion - The length assertion to evaluate

pub fn min(column: impl Into<String>, min_length: usize) -> Self

Creates a minimum length constraint.

pub fn max(column: impl Into<String>, max_length: usize) -> Self

Creates a maximum length constraint.

pub fn between( column: impl Into<String>, min_length: usize, max_length: usize, ) -> Self

Creates a length constraint that checks if the string length is between bounds (inclusive).

pub fn exactly(column: impl Into<String>, length: usize) -> Self

Creates a constraint that checks for exact length.

pub fn not_empty(column: impl Into<String>) -> Self

Creates a constraint that checks the string is not empty.

Trait Implementations

impl Clone for LengthConstraint

fn clone(&self) -> LengthConstraint

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Constraint for LengthConstraint

fn evaluate<'life0, 'life1, 'async_trait>( &'life0 self, ctx: &'life1 SessionContext, ) -> Pin<Box<dyn Future<Output = Result<ConstraintResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Evaluates the constraint against the data in the session context.

fn name(&self) -> &str

Returns the name of the constraint.

fn column(&self) -> Option<&str>

Returns the column this constraint operates on (if single-column).

fn description(&self) -> Option<&str>

Returns a description of what this constraint validates.

fn metadata(&self) -> ConstraintMetadata

Returns the metadata associated with this constraint.

impl Debug for LengthConstraint

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for LengthConstraint

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for LengthConstraint

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.