This commit is contained in:
Frederik Palmø 2023-05-24 22:24:43 +02:00
parent 66309d81db
commit 09cff01e0a
5 changed files with 41 additions and 24 deletions

2
Cargo.lock generated
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@ -4,4 +4,4 @@ version = 3
[[package]]
name = "eyes"
version = "1.3.1"
version = "1.3.0"

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@ -1,8 +1,8 @@
[package]
name = "eyes"
version = "1.3.1"
version = "1.3.0"
edition = "2018"
description = "A simpler way to parse using human-readable templates"
description = "Parse and convert strings using human-readable templates."
license="BSD-3-Clause"
homepage = "https://git.palmoe.dk/vodofrede/eyes/"
repository = "https://git.palmoe.dk/vodofrede/eyes/"

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@ -1,6 +1,6 @@
# eyes
A simpler way to parse using human-readable templates.
Parse and convert strings using human-readable templates.
The crate's primary purpose is parsing challenge inputs for [Advent of Code](https://adventofcode.com) challenges. It currently provides limited functionality, but more options may be added provided they are useful additions for parsing slightly more complicated formats.
@ -13,32 +13,42 @@ The only special characters in templates are curly brackets ('{}'). These act as
## Examples:
```rust
#[macro_use] extern crate eyes; // not normally necessary
fn main() {
use eyes::parse;
let input = "#lol @ 338,7643: 20.2x24.5";
let template = "#{} @ {},{}: {}x{}";
let (id, x, y, w, h) = eyes::parse!(input, template, String, isize, isize, f64, f64);
let (id, x, y, w, h) = parse!(input, template, String, isize, isize, f64, f64);
assert_eq!((id.as_str(), x, y, w, h), ("lol", 338, 7643, 20.2, 24.5));
}
```
**eyes** will try to expand capture groups, so that the following example also works as expected:
**eyes** will match capture groups greedily and expand them as far as possible, so that the following example also works as expected:
```rust
#[macro_use] extern crate eyes; // not normally necessary
fn main() {
use eyes::parse;
let input = "turn off 660,55 through 986,197";
let template = "{} {},{} through {},{}";
let (op, x1, y1, x2, y2) = eyes::parse!(input, template, String, usize, usize, usize, usize);
let (op, x1, y1, x2, y2) = parse!(input, template, String, usize, usize, usize, usize);
assert_eq!(
(op.as_str(), x1, y1, x2, y2),
("turn off", 660, 55, 986, 197)
);
}
```
Notice that "turn off" is captured correctly, even though it contains a space.
For error handling, the [`try_parse`] macro is provided which can be very useful in parsing potentially malformed input:
```rust
use eyes::try_parse;
let input = "1 2\n3,4\n5 6";
let result = input
.lines()
.filter_map(|line| try_parse!(line, "{} {}", i64, i64))
.collect::<Vec<_>>();
assert_eq!(vec![(1, 2), (5, 6)], result);
```

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@ -1,7 +1,12 @@
use eyes::parse;
fn main() {
if let Some((a, b, c)) = eyes::try_parse!("1 2,3", "{} {},{}", u8, u8, u8) {
assert!(a == 1 && b == 2 && c == 3);
} else {
unreachable!("This should not happen, as the pattern is matchable to the input");
}
let input = "1,2, 3";
parse!(input, "{},{}, {}", i64, i64, i64);
}

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@ -5,7 +5,7 @@
/// A list of captures, created by calling [`Captures::new()`] with the input and template strings.
///
/// An easier way to use this struct is with the [`eyes::parse`] and [`eyes::try_parse`] macros, which allow for automatic type conversion of captures.
/// An easier way to use this struct is with the [`parse`] and [`try_parse`] macros, which allow for automatic type conversion of captures.
pub struct Captures<'a> {
captures: Vec<&'a str>,
}
@ -137,7 +137,9 @@ macro_rules! try_parse {
#[macro_export]
macro_rules! parse {
($input: expr, $pattern: tt, $($type:ty),*) => {
{
$crate::try_parse!($input, $pattern, $($type),*).unwrap()
}
};
}