This crate provides handy implementations for some design pattern utilities.

Features

• Builderderive macro for appyling Builder pattern by generating extra Builder struct.
• Macro observer is for trait's and is for implementing Observer pattern by creating extra Publisher struct for the spesified instances whom implement this trait type.

Example

use patternutils::Builder;

#[derive(Builder)]
#[builder_attr(name = "CommandCreator", opt_in)]
struct Command {
    #[builder_field(name = "value", include = true)]
    definition: String,
    
    #[builder_field(include = true)]
    arg_count: usize,

    accepted_flag_fallback: fn(val: usize) -> usize,
    childs: Vec<Command>,
}

let mut builder = Command::builder();
let command = builder
    .value(String::from("my-command"))
    .arg_count(3)
    .build(|val| {return val + 5;}, vec![]);

assert_eq!(command.definition, String::from("my-command"));
assert_eq!(command.arg_count, 3);
assert_eq!((command.accepted_flag_fallback)(67), 72);
assert_eq!(command.childs.len(), 0);