//! A parser library designed for Advent of Code.
//!
//! This library mainly provides a macro, `parser!`, that lets you write
//! a custom parser for your [AoC] puzzle input in seconds.
//!
//! For example, my puzzle input for [December 2, 2015][example] looked like this:
//!
//! ```text
//! 4x23x21
//! 22x29x19
//! 11x4x11
//! 8x10x5
//! 24x18x16
//! ...
//! ```
//!
//! The parser for this format is a one-liner:
//! `parser!(lines(u64 "x" u64 "x" u64))`.
//!
//! # How to use aoc-parse
//!
//! **If you are NOT using [aoc-runner],** you can use aoc-parse like this:
//!
//! ```
//! use aoc_parse::{parser, prelude::*};
//!
//! let p = parser!(lines(u64 "x" u64 "x" u64));
//! assert_eq!(
//!     p.parse("4x23x21\n22x29x19\n").unwrap(),
//!     vec![(4, 23, 21), (22, 29, 19)]
//! );
//! ```
//!
//! **If you ARE using aoc-runner,** do this instead:
//!
//! ```
//! use aoc_runner_derive::*;
//!
//! #[aoc_generator(day2)]
//! fn parse_input(text: &str) -> anyhow::Result<Vec<(u64, u64, u64)>> {
//!     use aoc_parse::{parser, prelude::*};
//!     let p = parser!(lines(u64 "x" u64 "x" u64));
//!     aoc_parse(text, p)
//! }
//!
//! assert_eq!(
//!     parse_input("4x23x21\n22x29x19").unwrap(),
//!     vec![(4, 23, 21), (22, 29, 19)]
//! );
//! ```
//!
//! # Patterns
//!
//! The argument you need to pass to the `parser!` macro is a *pattern*;
//! all aoc-parse does is **match** strings against your chosen pattern
//! and **convert** them into Rust values.
//!
//! Here are the pieces that you can use in a pattern:
//!
//! *   `i8`, `i16`, `i32`, `i64`, `i128`, `isize` - These match an integer,
//!     written out using decimal digits, with an optional `+` or `-` sign
//!     at the start, like `0` or `-11474`.
//!
//!     It's an error if the string contains a number too big to fit in the
//!     type you chose. For example, `parser!(i8).parse("1000")` is an error.
//!     (It matches the string, but fails during the "convert" phase.)
//!
//! *   `u8`, `u16`, `u32`, `u64`, `u128`, `usize` - The same, but without
//!     the sign.
//!
//! *   `i8_bin`, `i16_bin`, `i32_bin`, `i64_bin`, `i128_bin`, `isize_bin`,
//!     `u8_bin`, `u16_bin`, `u32_bin`, `u64_bin`, `u128_bin`, `usize_bin`,
//!     `i8_hex`, `i16_hex`, `i32_hex`, `i64_hex`, `i128_hex`, `isize_hex`,
//!     `u8_hex`, `u16_hex`, `u32_hex`, `u64_hex`, `u128_hex`, `usize_hex` -
//!     Match an integer in base 2 or base 16. The `_hex` parsers allow both
//!     uppercase and lowercase digits `A`-`F`.
//!
//! *   `bool` - Matches either `true` or `false` and converts it to the
//!     corresponding `bool` value.
//!
//! *   `alpha`, `alnum`, `upper`, `lower` - Match single characters of
//!     various categories. (These use the Unicode categories, even though
//!     Advent of Code historically sticks to ASCII.)
//!
//! *   `digit`, `digit_bin`, `digit_hex` - Match a single ASCII character
//!     that's a digit in base 10, base 2, or base 16, respectively.
//!     The digit is converted to its numeric value, as a `usize`.
//!
//! *   `any_char`: Match the next character, no matter what it is (like `.`
//!     in a regular expression, except that `any_char` matches newline
//!     characters).
//!
//! *   `"x"` - A Rust string, in quotes, is a pattern that matches that exact
//!     string only.
//!
//!     Exact patterns don't produce a value.
//!
//! *   <code><var>pattern1 pattern2 pattern3</var>...</code> - Patterns can be
//!     concatenated to form larger patterns. This is how
//!     `parser!(u64 "x" u64 "x" u64)` matches the string `4x23x21`. It simply
//!     matches each subpattern in order. It converts the match to a tuple if
//!     there are two or more subpatterns that produce values.
//!
//! *   <code><var>parser_var</var></code> - You can use previously defined
//!     parsers that you've stored in local variables.
//!
//!     For example, the `amount` parser below makes use of the `fraction` parser
//!     defined on the previous line.
//!
//!     ```
//!     # use aoc_parse::{parser, prelude::*};
//!     let fraction = parser!(i64 "/" u64);
//!     let amount = parser!(fraction " tsp");
//!
//!     assert_eq!(amount.parse("1/4 tsp").unwrap(), (1, 4));
//!     ```
//!
//! *   <code>string(<var>pattern</var>)</code> - Matches the given *pattern*,
//!     but instead of converting it to some value, simply return the matched
//!     characters as a `String`.
//!
//!     By default, `alpha+` returns a `Vec<char>`, and sometimes that is handy
//!     in AoC, but often it's better to have it return a `String`.
//!
//! Repeating patterns:
//!
//! *   <code><var>pattern</var>*</code> - Any pattern followed by an asterisk
//!     matches that pattern zero or more times. It converts the results to a
//!     `Vec`. For example, `parser!("A"*)` matches the strings `A`, `AA`,
//!     `AAAAAAAAAAAAAA`, and so on, as well as the empty string.
//!
//! *   <code><var>pattern</var>+</code> - Matches the pattern one or more times, producing a `Vec`.
//!     `parser!("A"+)` matches `A`, `AA`, etc., but not the empty string.
//!
//! *   <code><var>pattern</var>?</code> - Optional pattern, producing a Rust `Option`. For
//!     example, `parser!("x=" i32?)` matches `x=123`, producing `Some(123)`;
//!     it also matches `x=`, producing the value `None`.
//!
//!     These behave just like the `*`, `+`, and `?` special characters in
//!     regular expressions.
//!
//! *   <code>repeat_sep(<var>pattern</var>, <var>separator</var>)</code> -
//!     Match the given *pattern* any number of times, separated by the *separator*.
//!     This converts only the bits that match *pattern* to Rust values, producing
//!     a `Vec`. Any parts of the string matched by *separator* are not converted.
//!
//! *   <code>lines(<var>pattern</var>)</code> - Matches any number of lines of
//!     text matching *pattern*. Each line must be terminated by a newline, `'\n'`.
//!
//! Custom conversion:
//!
//! *   <code>... (<var>name1</var>: <var>pattern1</var>) ... => <var>expr</var></code> -
//!     On successfully matching the patterns to the left of `=>`, evaluate the Rust
//!     expression *expr* to convert the results to a single Rust value.
//!
//!     Use this to convert input to structs or enums. For example, suppose we have
//!     input that looks like `(3,66)-(27,8)` and we want to produce these structs:
//!
//!     ```
//!     #[derive(Debug, PartialEq)]
//!     struct Point(i64, i64);
//!
//!     #[derive(Debug, PartialEq)]
//!     struct Line {
//!         p1: Point,
//!         p2: Point,
//!     }
//!     ```
//!
//!     The patterns we need are:
//!
//!     ```
//!     # use aoc_parse::{parser, prelude::*};
//!     # #[derive(Debug, PartialEq)]
//!     # struct Point(i64, i64);
//!     #
//!     # #[derive(Debug, PartialEq)]
//!     # struct Line {
//!     #     p1: Point,
//!     #     p2: Point,
//!     # }
//!     let point = parser!("(" (x: i64) "," (y: i64) ")" => Point(x, y));
//!     let line_parser = parser!((p1: point) "-" (p2: point) => Line { p1, p2 });
//!
//!     assert_eq!(
//!         line_parser.parse("(3,66)-(27,8)").unwrap(),
//!         Line { p1: Point(3, 66), p2: Point(27, 8) },
//!     );
//!     ```
//!
//! Patterns with two or more alternatives:
//!
//! *   <code>{<var>pattern1</var>, <var>pattern2</var>, ...}</code> -
//!     First try matching *pattern1*; if it matches, stop. If not, try
//!     *pattern2*, and so on. All the patterns must produce the same type of
//!     Rust value.
//!
//!     For example, `parser!({"<" => -1, ">" => 1})` either matches `<`,
//!     returning the value `-1`, or matches `>`, returing `1`.
//!
//! [AoC]: https://adventofcode.com/
//! [example]: https://adventofcode.com/2015/day/2
//! [aoc-runner]: https://lib.rs/crates/aoc-runner

mod error;
pub mod functions;
pub mod macros;
mod parsers;
mod types;

pub use error::ParseError;
use error::Result;
pub use parsers::{ParseIter, Parser};
use types::ParserOutput;

pub mod prelude {
    pub use crate::functions::{line, lines, repeat_sep, string};
    pub use crate::parsers::{
        alnum, alpha, any_char, aoc_parse, bool, digit, digit_bin, digit_hex, i128, i128_bin,
        i128_hex, i16, i16_bin, i16_hex, i32, i32_bin, i32_hex, i64, i64_bin, i64_hex, i8, i8_bin,
        i8_hex, isize, isize_bin, isize_hex, lower, u128, u128_bin, u128_hex, u16, u16_bin,
        u16_hex, u32, u32_bin, u32_hex, u64, u64_bin, u64_hex, u8, u8_bin, u8_hex, upper, usize,
        usize_bin, usize_hex, Parser,
    };
}