genco 0.14.1

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# genco

A whitespace-aware quasiquoter for beautiful code generation.

Central to genco are the [quote!] and [quote_in!] procedural macros which
ease the construction of [token streams].

This project solves the following language-specific concerns:

* **Imports** — Generates and groups [import statements] as they are used.
  So you only import what you use, with no redundancy. We also do our best
  to [solve namespace conflicts].

* **String Quoting** — genco knows how to [quote strings]. And can even
  [interpolate] values *into* the quoted string if it's supported by the
  language.

* **Structural Indentation** — The quoter relies on intuitive
  [whitespace detection] to structurally sort out spacings and indentation.
  Allowing genco to generate beautiful readable code with minimal effort.
  This is also a requirement for generating correctly behaving code in
  languages like Python where [indentation is meaningful].

* **Language Customization** — Building support for new languages is a
  piece of cake with the help of the [impl_lang!] macro.

<br>

To do [whitespace detection], we depend on the nightly
[`proc_macro_span` feature].

*Until this is stabilized*, you must build and run projects using genco
with a `nightly` compiler.

```bash
cargo +nightly run --example rust
```

[`proc_macro_span` feature]: https://github.com/rust-lang/rust/issues/54725

<br>

### Supported Languages

The following are languages which have built-in support in genco.

* [🦀 <b>Rust</b>][rust]<br>
  <small>[Example][rust-example]</small>

* [☕ <b>Java</b>][java]<br>
  <small>[Example][java-example]</small>

* [🎼 <b>C#</b>][c#]<br>
  <small>[Example][c#-example]</small>

* [🐿️ <b>Go</b>][go]<br>
  <small>[Example][go-example]</small>

* [🎯 <b>Dart</b>][dart]<br>
  <small>[Example][dart-example]</small>

* [🌐 <b>JavaScript</b>][js]<br>
  <small>[Example][js-example]</small>

* [🐍 <b>Python</b>][python]<br>
  <small>[Example][python-example]</small>

<small>Is your favorite language missing? <b>[Open an issue!]</b></small>

You can run one of the examples by:

```bash
cargo +nightly run --example rust
```

<br>

### Rust Example

The following is a simple program producing Rust code to stdout with custom
configuration:

```rust
use genco::prelude::*;

let hash_map = rust::import("std::collections", "HashMap");

let tokens: rust::Tokens = quote! {
    fn main() {
        let mut m = #hash_map::new();
        m.insert(1u32, 2u32);
    }
};

println!("{}", tokens.to_file_string()?);
```

This would produce:

```rust
use std::collections::HashMap;

fn main() {
    let mut m = HashMap::new();
    m.insert(1u32, 2u32);
}
```

<br>

[rust]: https://docs.rs/genco/0/genco/lang/rust/index.html
[rust-example]: https://github.com/udoprog/genco/blob/master/examples/rust.rs
[java]: https://docs.rs/genco/0/genco/lang/java/index.html
[java-example]: https://github.com/udoprog/genco/blob/master/examples/java.rs
[c#]: https://docs.rs/genco/0/genco/lang/csharp/index.html
[c#-example]: https://github.com/udoprog/genco/blob/master/examples/csharp.rs
[go]: https://docs.rs/genco/0/genco/lang/go/index.html
[go-example]: https://github.com/udoprog/genco/blob/master/examples/go.rs
[dart]: https://docs.rs/genco/0/genco/lang/dart/index.html
[dart-example]: https://github.com/udoprog/genco/blob/master/examples/dart.rs
[js]: https://docs.rs/genco/0/genco/lang/js/index.html
[js-example]: https://github.com/udoprog/genco/blob/master/examples/js.rs
[python]: https://docs.rs/genco/0/genco/lang/python/index.html
[python-example]: https://github.com/udoprog/genco/blob/master/examples/python.rs
[solve namespace conflicts]: file:///home/udoprog/repo/genco/target/doc/genco/lang/csharp/fn.import.html
[indentation is meaningful]: https://docs.python.org/3/faq/design.html#why-does-python-use-indentation-for-grouping-of-statements
[token streams]: https://docs.rs/genco/0/genco/tokens/struct.Tokens.html
[import statements]: https://docs.rs/genco/0/genco/macro.quote.html#imports
[quote strings]: https://docs.rs/genco/0/genco/macro.quote.html#string-quoting
[interpolate]: https://docs.rs/genco/0/genco/macro.quote.html#quoted-string-interpolation
[whitespace detection]: https://docs.rs/genco/0/genco/macro.quote.html#whitespace-detection
[quote!]: https://docs.rs/genco/0/genco/macro.quote.html
[quote_in!]: https://docs.rs/genco/0/genco/macro.quote_in.html
[impl_lang!]: https://docs.rs/genco/0/genco/macro.impl_lang.html
[quoted()]: https://docs.rs/genco/0/genco/tokens/fn.quoted.html
[Open an issue!]: https://github.com/udoprog/genco/issues/new