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//! This is Rust quasi-quoting library like [quote](quote) that gives you `mquote!` macro providing
//! several features aimed on better readability and usability. It supports:
//! * [expression insertion](#expression-insertion)
//! * [**if/else**](#if--elif--else) condition
//! * [**for**](#for) iteration
//! * [**match**](#matching)ing
//! * [**extend**](#extending)ing
//!
//! ## Example
//! ```rust
//! # use mquote::mquote;
//! # let having_fun = true;
//! mquote!{
//! #{if having_fun}
//! fn funny_method() { ... }
//! #{endif}
//! fn regular_method() { ... }
//! };
//! ```
//!
//! Crate contains `mquote!` and `mquote_spanned!`. Usage examples of the first one
//! are [below](#expression-insertion). The second one allow you to set
//! span of producing tokens stream by this syntax: `mquote_spanned!(span => ...)`.
//!
//! ## Expression insertion
//! Turns given expression into tokens by using [`ToTokens`](../quote/trait.ToTokens.html).
//! ```rust
//! # use mquote::mquote;
//! # struct Person { name: &'static str, age: u16 }
//! fn put_filter(enabled: bool) -> proc_macro2::TokenStream {
//! let good_person = Person{ name: "Oleg", age: 20 };
//! mquote!{
//! assert!(!#{enabled} || person.name == #{good_person.name}
//! && person.age >= #{good_person.age})
//! }
//! }
//! ```
//!
//! ## If / elif / else
//! ```rust
//! # use mquote::mquote;
//! fn define_container(amount: usize) -> proc_macro2::TokenStream {
//! mquote!{
//! #{if amount > 1}
//! struct People(Vec<Person>);
//! #{elif amount == 1}
//! struct Human(Person);
//! #{else}
//! struct NoneHuman;
//! #{endif}
//! }
//! }
//! ```
//!
//! ## For
//! ```rust
//! # use mquote::mquote;
//! # use proc_macro2::Ident;
//! fn define_person(fields: Vec<(Ident, Ident)>) -> proc_macro2::TokenStream {
//! mquote!{
//! pub struct Person {
//! #{for (name, ty) in fields}
//! #{name}: #{ty}
//! #{endfor}
//! }
//! }
//! }
//! ```
//!
//! ## Matching
//! ```rust
//! # use mquote::mquote;
//! # use proc_macro2::Ident;
//! fn hardcode_it(var: Ident, value: Option<&str>) -> proc_macro2::TokenStream {
//! mquote!{
//! static #var: &str = #{match value}
//! #{of Some(x) if x.len() > 0}
//! #{x};
//! #{of Some(_)}
//! "case for empty strings";
//! #{of None}
//! "default value";
//! #{endmatch}
//! }
//! }
//! ```
//!
//! ## Extending
//! Sometimes you want `mquote!` to consume an iterator of `TokenTree`s
//! without cloning. It's possible with special syntax `^{iterable}` that accepts
//! any `IntoIterator<Item=TokenTree>`.
//!
//! ```rust
//! # use mquote::mquote;
//! # use proc_macro2::TokenStream;
//! fn assign_by_ref(stream: TokenStream) -> TokenStream {
//! let tail = stream.into_iter().skip(5); // here could be something
//! // more reasonable
//! mquote!{
//! let _ = ^{tail}
//! }
//! }
//! ```
//!
//! ## Escaping `#{}` or `^{}`
//! If you want to put either `#{abc}` or `^{abc}` as is, you should double braces:
//! ```rust
//! # use mquote::mquote;
//! fn it_works() {
//! let tokens = mquote!(#{{abc}} ^{{abc}});
//! assert_eq!(tokens.to_string(), "# { abc } ^ { abc }")
//! }
//! ```
extern crate mquote_impl;
extern crate proc_macro_hack;
extern crate quote;
extern crate proc_macro2;
use proc_macro_hack;
/// Turns given directives into [TokenStream](../proc_macro2/struct.TokenStream.html).
///
/// You may learn syntax in [root level documentation](index.html).
pub use mquote;
/// Same as [mquote!](macro.mquote.html), but applies a given span to all tokens originating within the macro invocation.
///
/// ## Example
/// ```rust
/// # use mquote::mquote_spanned;
/// let span = proc_macro2::Span::call_site();
/// mquote_spanned!(span => let _ = Some(12));
/// ```
pub use mquote_spanned;