later_operator 0.4.2

Parsable, storable, printable comparison operators, w/ optional serde support.
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# Later Operator

[![docs.rs](https://img.shields.io/docsrs/later_operator.svg?style=flat-square&label=docs.rs)](https://docs.rs/later_operator/)
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This library provides a `ComparisonOperator` enum that can be used to parse, store, evaluate, and/or print Rust's relational operators: `!=`, `<`, `<=`, `==`, `>=`, `>`.



## Examples

```rust
use later_operator::ComparisonOperator;

// Parse from a string, then compare two arbitrary values.
let op = ComparisonOperator::try_from("<=").unwrap();
assert!(op.compare(&3_u8, &u8::MAX)); // 3 <= 255

// Re-stringify the operator for printing or whatever.
assert_eq!(
    format!("3 {op} 255"),
    "3 <= 255",
);

// Leading/trailing whitespace is ignored when parsing.
assert_eq!(
    ComparisonOperator::try_from("==").unwrap(),
    ComparisonOperator::try_from(" ==\n").unwrap(),
);

// But the value has to make sense or it will fail.
assert!(ComparisonOperator::try_from("~").is_err());
```

When the optional `serde` crate feature is enabled, `ComparisonOperator` can be de/serialized as a string too:

```rust
use later_operator::ComparisonOperator;
use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Deserialize, Serialize)]
struct AffectedVersion {
    operator: ComparisonOperator,
    version: String,
}
```



## Installation

Add `later_operator` to your `dependencies` in `Cargo.toml`, like:

```toml
[dependencies]
later_operator = "0.4.*"
```