A crate to format and print strings with an embedded rust expression.

Examples

Using :? modifier.

use expression_format::ex_format;
let v = vec![1, 2, 3];
assert_eq!(ex_format!("v = {:?v}"), "v = [1, 2, 3]");

Printing the contents of fields.

use expression_format::ex_format;
let arg = ["ipsum", "sit"];
assert_eq!(ex_format!("lorem {arg[0]} dolor {arg[1]} amet"), "lorem ipsum dolor sit amet");

Short version of ex_format! with a complex expression.

use expression_format::short::exf;

assert_eq!(
exf!(r#"Hello { { // Space after the first { since {{ is an escape sequence.
let first = "Wo";
let second = "rld";
let mut result = String::from(first);
result.push_str(second);
result
}}!"#),
"Hello World!"
);

Print to standard output with a new line.

use expression_format::short::expl; // Short name version of ex_println!
#[derive(Debug)]
struct Point {x: i32, y: i32}

expl!("value of point = {:?Point {x: 1 + 2, y: 3 * 4 }}");
// stdout: value of point = Point { x: 3, y: 12 }

Escape brackets with {{ and }}.

use expression_format::short::exf;
let value = 10;
assert_eq!(exf!("{{value}} = {value}"), "{value} = 10");