Crate yash_arith

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Expand description

This crate implements shell arithmetic expansion.

Arithmetic expansion evaluates an expression that may contain some operators that perform basic maths. The expression is given as a string and parsed like an expression in C. The expression can include variables that interact with the environment.

To evaluate an expression, you call the eval() function with a string and an environment.

use std::collections::HashMap;
use yash_arith::{eval, Value};
let mut env = HashMap::new();
env.insert("a".to_owned(), "2".to_owned());
let result = eval("1 + a", &mut env);
assert_eq!(result, Ok(Value::Integer(3)));


  • Description of an error that occurred during expansion



  • Interface for accessing variables during evaluation


  • Performs arithmetic expansion