A Rust library for generically joining iterables with a separator. Provides the tragically missing string join functionality to rust.
```rust extern crate joinery;
use std::env;
// Or use joinery::prelude::*; use joinery::Joinable;
fn main() { // Join things! println!("{}", ["Hello", "World!"].iter().join_with(", "));
// Join things of different types!
println!("{}", ["Hello", "World!"].iter().join_with(' '));
println!("{}", (0..10).join_with(' '));
} ```
Add joinery to your Cargo.toml
:
toml
[dependencies]
joinery = "0.1.0"
joinery supports various nightly-only optimization features, such as iter::TrustedLen
and Iterator::try_fold
(which requires ops::Try
). These features are enabled with the "nightly"
cargo feature:
toml
[dependencies.joinery]
version = "0.1.0"
features = ["nightly"]
Note that, because nightly-only features are unstable, joinery can't make any stability guarentees about their continued presence or interface consistency between versions. While we'll do our best to preserve compatibility, we only guarentee semver compatibility for the non-nightly interface.
Joinery provides joins over iterators. Put simply, a join is a combination of an iterator and a separator. The join then conceptually represents all the elemetns of the iterator, with the separator between each one.
You can create a join with the join_with
method, which is defined for all IntoIterator
types via the Joinable
trait:
```rust use joinery::prelude::*;
let content = vec![1, 2, 3, 4, 5];
let join = content.iter().join_with(", "); ```
Joins implement Display
, so they can be written to writers or converted into strings. Joins are stateless, so they can be reused, assuming that the underlying iterator is cloneable:
```rust println!("Comma-separated numbers: {}", join);
let mut result = String::new(); write!(&mut result, "{}", join);
// Don't forget that Display
gives you ToString
for free!
let result2 = join.to_string();
```
Joins are also iterable. You can use .iter()
to iterate over references to the underlying iterator, or into_iter()
to convert the join into an iterator. Join iterators use an item type called JoinItem
, which distinguishes between separators and elements of the underlying iterator:
```rust use joinery::JoinItem; let mut iter = join.iter();
asserteq!(iter.next(), Some(JoinItem::Element(&1))); asserteq!(iter.next(), Some(JoinItem::Separator(&", "))); asserteq!(iter.next(), Some(JoinItem::Element(&2))); asserteq!(iter.next(), Some(JoinItem::Separator(&", "))); assert_eq!(iter.next(), Some(JoinItem::Element(&3))); ```
See the docs for complete documentation, including many more examples.