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//! A simple macro allowing for clean do-while loops in Rust.
//!
//! Basic usage:
//! ```rust
//! use do_while::do_while;
//!
//! let mut x = 0;
//! do_while! {
//! do {
//! x += 1;
//! } while x < 10;
//! }
//! assert_eq!(x, 10);
//! ```
//!
//! For more advanced details and usage, see the macro-level documentation for [do_while].
/// A macro allowing for clean do-while loops.
///
/// The basic syntax is:
/// ```rust
/// use do_while::do_while;
/// # let condition = false;
/// # fn do_stuff() {}
///
/// do_while! {
/// do {
/// do_stuff();
/// } while condition;
/// }
/// ```
///
/// This expands to:
/// ```rust
/// # let condition = false;
/// # fn do_stuff() {}
/// while {
/// do_stuff();
/// condition
/// } {}
/// ```
/// The body of the do-while loop is placed inside the condition expression of the while loop,
/// meaning it runs before the condition is evaluated, and the actual body of the while loop is left
/// empty. The `do_while` macro allows for this to be expressed in a cleaner and more obvious fashion.
///
/// 'Do-while-do' loops, with code in _both_ the condition and the body of the expanded while loop,
/// are also possible.
/// ```rust
/// use do_while::do_while;
/// # let condition = false;
/// # fn do_stuff() {}
/// # fn do_more_stuff() {}
///
/// do_while! {
/// do {
/// do_stuff();
/// } while condition, do {
/// do_more_stuff();
/// }
/// }
/// ```
/// This expands to:
/// ```rust
/// # let condition = false;
/// # fn do_stuff() {}
/// # fn do_more_stuff() {}
/// while {
/// do_stuff();
/// condition
/// } {
/// do_more_stuff();
/// }
/// ```
/// Multiple loops within the same macro invocation are also possible.
///
/// ## Examples
///
/// Simple do-while loop:
/// ```rust
/// use do_while::do_while;
///
/// let mut x = 0;
/// do_while! {
/// do {
/// x += 1;
/// } while x < 10;
/// }
/// assert_eq!(x, 10);
/// ```
///
/// Custom list formatting with a do-while-do loop:
/// ```rust
/// use do_while::do_while;
///
/// let items = vec![1, 2, 3, 4];
/// let mut string = String::new();
///
/// let mut index: usize = 0;
/// do_while! {
/// do {
/// string.push_str(&items[index].to_string());
/// index += 1;
/// } while index < items.len(), do {
/// string.push_str(", ");
/// }
/// }
///
/// assert_eq!(string, "1, 2, 3, 4".to_string());
/// ```
///
/// Multiple loops at once:
/// Multiple do-while and do-while-do loops can be mixed and matched in the same macro invocation:
/// ```rust
/// use do_while::do_while;
///
/// let mut x = 0;
/// let mut y = 0;
///
/// let list = vec![5, 6, 7, 8];
/// let mut string = String::new();
/// let mut index: usize = 0;
///
/// do_while! {
/// do {
/// x += 1;
/// } while x < 10;
///
/// do {
/// y -= 1;
/// } while y > -20;
///
/// do {
/// string.push_str(&list[index].to_string());
/// index += 1;
/// } while index < list.len(), do {
/// string.push_str(", ");
/// }
/// }
///
/// assert_eq!(x, 10);
/// assert_eq!(y, -20);
/// assert_eq!(string, "5, 6, 7, 8".to_string());
/// ```