Function dynparser::peg::rules_from_peg

pub fn rules_from_peg(peg: &str) -> Result

Given a peg set of rules on an string, it will generate the set of rules to use in the parser

Next, is a full example showing the error messages, if so

extern crate dynparser;
use dynparser::{parse, rules_from_peg};

fn main() {
    let rules = rules_from_peg(
        r#"
main    =   'hello'   ' '   'world'  dot
dot     =   "\0x2E"
        "#,
    ).map_err(|e| {
        println!("{}", e);
        panic!("FAIL");
    })
        .unwrap();

    println!("{:#?}", rules);

    let result = parse("hello world.", &rules);

    assert!(result.is_ok());

    match result {
        Ok(ast) => println!("{:#?}", ast),
        Err(e) => println!("Error: {:?}", e),
    };
}

Next is an example with some and literals and comments on peg grammar

extern crate dynparser;
use dynparser::{parse, rules_from_peg};

   let rules = rules_from_peg(
       r#"
        //  classic hello world
        main    =   'hello'   ' '   'world'

        /*  with a multiline comment
        */
       "#,
   ).unwrap();

    assert!(parse("hello world", &rules).is_ok());

Next is an example with some error info

   extern crate dynparser;
   use dynparser::{parse, rules_from_peg};

   let rules = rules_from_peg(
       r#"
        main    =   '('  main  ( ')'  /  error("unbalanced parenthesys") )
                /   'hello'
       "#,
   ).unwrap();

    assert!(parse("hello", &rules).is_ok());
    println!("{:?}", parse("(hello)", &rules));
    assert!(parse("(hello)", &rules).is_ok());
    assert!(parse("((hello))", &rules).is_ok());
    assert!(parse("(((hello)))", &rules).is_ok());
    match parse("(hello", &rules) {
        Err(e) => {assert!(e.descr == "unbalanced parenthesys");},
        _ => ()
    }
    match parse("((hello)", &rules) {
        Err(e) => {assert!(e.descr == "unbalanced parenthesys");},
        _ => ()
    }