Function dynamic_format 

pub fn dynamic_format(
    pattern: &str,
    dictionary: &HashMap<&str, &str>,
) -> Result<String, Box<DynamicFormatError>>

Lightweight, dynamic, Python-styled string formatting (Only support String, {key} patterns). It only needs std to work.

Escape patterns are {{ and }}.

It returns the formatted string.

Errors

1. Error kind DynamicFormatErrorKind::KeyError if the key in the brackets is not found in dictionary.
2. Error kind DynamicFormatErrorKind::TokenError if there is any unmatched bracket ({ or })

Examples

use dyn_formatting::dynamic_format;
assert_eq!(
    dynamic_format(
        "I'm {name}. I'm {age} years old now.",
        &[("name", "ABC"), ("age", "20")].into()
    ).unwrap(),
    "I'm ABC. I'm 20 years old now.".to_string()
);

use dyn_formatting::dynamic_format;
use std::collections::HashMap;

let value_age = (15).to_string(); // Make lifetime long enough
let dictionary = HashMap::from([
    ("age", value_age.as_str()),
]);
assert_eq!(
    dynamic_format("{{{age} }}{age}", &dictionary).unwrap(),
    "{15 }15"
)

use dyn_formatting::dynamic_format;
assert!(
    dynamic_format(
        "I'm {name}. I'm {age} years old now.",
        &[("name", "ABC")].into()
    ).is_err() // Key error
);

use dyn_formatting::dynamic_format;
assert!(
    dynamic_format(
        "I'm {name{name}}.",
        &[("name", "ABC")].into()
    ).is_err() // Token error: '{' unmatched.
);