Constrained Inputs

Constrained Inputs is a Rust crate that simplifies the process of handling user input with specific type constraints and validations. This crate provides a mechanism to define and apply constraints to ensure that user inputs meet certain criteria before being accepted.

Features

• Easy-to-use input parsing and prompting
• Customizable constraints for strings and numbers
• Detailed error handling for invalid inputs and constraint violations

Usage

Basic Input Parsing

You can use the input function to parse user input directly into a specified type.

use constrained_inputs::input;

fn main() {
    let int: i32 = input().expect("Input was invalid");
    println!("Your input integer: {}", int);
}

Constrained Input Parsing

Use the constrained_input function to prompt user input with additional constraints.

use constrained_inputs::{constrained_input, constraints::NumberConstraint};

fn main() {
    let constraint = NumberConstraint {
        max: Some(100),
        min: Some(10),
    };
    let int: i32 = constrained_input(constraint).expect("Input was invalid or out of range");
    println!("Your constrained input integer: {}", int);
}

Constraints

The constraints module provides various constraint configurations that can be applied to user inputs. These include constraints for strings and numbers.

String Constraints

Define constraints on strings, such as maximum length, minimum length, and blacklisted characters.

use constrained_inputs::constraints::{StringConstraint, Constraint, ConstraintResult, ConstraintError};

fn main() {
    let string_constraint = StringConstraint {
        max_len: Some(10),
        min_len: Some(5),
        blacklist_chars: vec!['a', 'e', 'i', 'o', 'u'],
    };

    let result = string_constraint.validate(&"hello");
    assert_eq!(result, ConstraintResult::Err(ConstraintError::BlacklistedChar));
}

Number Constraints

Define constraints on numbers, such as maximum and minimum values.

use constrained_inputs::constraints::{NumberConstraint, Constraint, ConstraintResult};

fn main() {
    let number_constraint = NumberConstraint {
        max: Some(100),
        min: Some(10),
    };

    let result = number_constraint.validate(&50);
    assert_eq!(result, ConstraintResult::Valid);
}

Input Stream

A function that reads in a stream of data from a bufreader.

fn main() {
    let cursor = io::Cursor::new("123");

    let res = input_stream::<i32, _>(cursor);

    assert_eq!(123, res.unwrap());
}