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-rw-r--r--improved_slice_patterns/Cargo.toml10
-rw-r--r--improved_slice_patterns/README.md30
-rw-r--r--improved_slice_patterns/src/lib.rs316
3 files changed, 0 insertions, 356 deletions
diff --git a/improved_slice_patterns/Cargo.toml b/improved_slice_patterns/Cargo.toml
deleted file mode 100644
index a5815e8..0000000
--- a/improved_slice_patterns/Cargo.toml
+++ /dev/null
@@ -1,10 +0,0 @@
-[package]
-name = "improved_slice_patterns"
-version = "2.0.0" # remember to update html_root_url
-authors = ["Nadrieril <nadrieril@users.noreply.github.com>"]
-license = "MIT OR Apache-2.0"
-edition = "2018"
-description = "A tiny crate that provides macros to help matching on Vecs and iterators using the syntax of slice_patterns"
-readme = "README.md"
-repository = "https://github.com/Nadrieril/dhall-rust"
-documentation = "https://docs.rs/improved_slice_patterns/"
diff --git a/improved_slice_patterns/README.md b/improved_slice_patterns/README.md
deleted file mode 100644
index 7f07530..0000000
--- a/improved_slice_patterns/README.md
+++ /dev/null
@@ -1,30 +0,0 @@
-# `improved_slice_patterns`
-
-A tiny crate that provides two macros to help matching
-on `Vec`s and iterators using the syntax of [`slice_patterns`][slice_patterns]
-
-[slice_patterns]: https://doc.rust-lang.org/nightly/unstable-book/language-features/slice-patterns.html
-
-## Changelog
-
-### V2.0
-
-- `match_vec` now returns a `Result` instead of an `Option`. The `Err` variant
-is used to return ownership of the passed vec if there was no match.
-
-## License
-
-Licensed under either of
-
- * Apache License, Version 2.0
- (http://www.apache.org/licenses/LICENSE-2.0)
- * MIT license
- (http://opensource.org/licenses/MIT)
-
-at your option.
-
-## Contribution
-
-Unless you explicitly state otherwise, any contribution intentionally submitted
-for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
-dual licensed as above, without any additional terms or conditions
diff --git a/improved_slice_patterns/src/lib.rs b/improved_slice_patterns/src/lib.rs
deleted file mode 100644
index 56ea54a..0000000
--- a/improved_slice_patterns/src/lib.rs
+++ /dev/null
@@ -1,316 +0,0 @@
-#![doc(html_root_url = "https://docs.rs/improved_slice_patterns/2.0.0")]
-
-//! A tiny crate that provides two macros to help matching
-//! on `Vec`s and iterators using the syntax of
-//! [`slice_patterns`][slice_patterns]
-//!
-//! [slice_patterns]: https://doc.rust-lang.org/nightly/unstable-book/language-features/slice-patterns.html
-
-/// Destructure an iterator using the syntax of slice_patterns.
-///
-/// Wraps the match body in `Some` if there was a match; returns
-/// `None` otherwise.
-///
-/// Contrary to slice_patterns, this allows moving out
-/// of the iterator.
-///
-/// A variable length pattern (`x @ ..`) is only allowed as the last
-/// pattern, unless the iterator is double-ended.
-///
-/// Example:
-/// ```edition2018
-/// use improved_slice_patterns::destructure_iter;
-///
-/// let vec = vec![Some(1), Some(2), Some(3), None];
-///
-/// let res = destructure_iter!(vec.into_iter();
-/// [Some(x), y @ .., z] => {
-/// // x: usize
-/// // y: impl Iterator<Option<usize>>
-/// // z: Option<usize>
-/// (x, y.collect::<Vec<_>>(), z)
-/// }
-/// );
-///
-/// assert_eq!(res, Some((1, vec![Some(2), Some(3)], None)));
-///
-/// # Ok::<(), ()>(())
-/// ```
-///
-///
-#[macro_export]
-macro_rules! destructure_iter {
- // Variable length pattern
- (@match_forwards, $iter:expr, ($body:expr),
- $x:ident @ .., $($rest:tt)*) => {
- $crate::destructure_iter!(@match_backwards,
- $iter,
- ({
- let $x = $iter;
- $body
- }),
- $($rest)*
- )
- };
- // Special variable length pattern with a common unary variant
- (@match_forwards, $iter:expr, ($body:expr),
- $variant:ident ($x:ident).., $($rest:tt)*) => {
- $crate::destructure_iter!(@match_backwards,
- $iter,
- ({
- let $x = $iter
- .map(|x| match x {
- $variant(y) => y,
- _ => unreachable!(),
- });
- $body
- }),
- $($rest)*
- )
- };
- // Variable length pattern without a binder
- (@match_forwards, $iter:expr, ($body:expr), .., $($rest:tt)*) => {
- $crate::destructure_iter!(@match_backwards,
- $iter,
- ($body),
- $($rest)*
- )
- };
- // Single item pattern
- (@match_forwards, $iter:expr, ($body:expr), $x:pat, $($rest:tt)*) => {
- if let std::option::Option::Some($x) = $iter.next() {
- $crate::destructure_iter!(@match_forwards,
- $iter,
- ($body),
- $($rest)*
- )
- } else {
- std::option::Option::None
- }
- };
- // Single item pattern after a variable length one: declare reversed and take from the end
- (@match_backwards, $iter:expr, ($body:expr), $x:pat, $($rest:tt)*) => {
- $crate::destructure_iter!(@match_backwards, $iter, (
- if let std::option::Option::Some($x) = $iter.next_back() {
- $body
- } else {
- std::option::Option::None
- }
- ), $($rest)*)
- };
-
- // Check no elements remain
- (@match_forwards, $iter:expr, ($body:expr) $(,)*) => {
- if $iter.next().is_some() {
- std::option::Option::None
- } else {
- $body
- }
- };
- // After a variable length pattern, everything has already been consumed
- (@match_backwards, $iter:expr, ($body:expr) $(,)*) => {
- $body
- };
-
- ($iter:expr; [$($args:tt)*] => $body:expr) => {
- {
- #[allow(unused_mut)]
- let mut iter = $iter;
- $crate::destructure_iter!(@match_forwards,
- iter,
- (std::option::Option::Some($body)),
- $($args)*,
- )
- }
- };
-}
-
-/// Pattern-match on a vec using the syntax of slice_patterns.
-///
-/// Wraps the match body in `Ok` if there was a match; returns
-/// an `Err` containing the ownership of the vec otherwise.
-///
-/// Contrary to slice_patterns, this allows moving out
-/// of the `Vec`.
-///
-/// A variable length pattern (`x @ ..`) returns an iterator.
-///
-/// Example:
-/// ```edition2018
-/// #![feature(slice_patterns)]
-/// use improved_slice_patterns::match_vec;
-///
-/// let vec = vec![Some(1), Some(2), Some(3), None];
-///
-/// let res = match_vec!(vec;
-/// [Some(_), y @ .., None] => {
-/// y.collect::<Vec<_>>()
-/// },
-/// [None, None] => {
-/// vec![]
-/// },
-/// [..] => vec![]
-/// );
-///
-/// assert_eq!(res, Ok(vec![Some(2), Some(3)]));
-///
-///
-/// let vec = vec![Some(1), Some(2), Some(3), None];
-///
-/// let res = match_vec!(vec;
-/// [Some(_), y @ .., Some(_)] => {
-/// y.collect::<Vec<_>>()
-/// },
-/// [None, None] => {
-/// vec![]
-/// },
-/// );
-///
-/// assert!(res.is_err()); // there was no match
-///
-/// # Ok::<(), ()>(())
-/// ```
-///
-///
-#[macro_export]
-macro_rules! match_vec {
- // Variable length pattern
- (@make_pat; ($($acc:tt)*), $x:ident @ .., $($rest:tt)*) => {
- $crate::match_vec!(@make_pat;
- ($($acc)*, $x @ ..),
- $($rest)*
- )
- };
- // Special variable length pattern with a common unary variant
- (@make_pat; ($($acc:tt)*), $variant:ident ($x:ident).., $($rest:tt)*) => {
- $crate::match_vec!(@make_pat;
- ($($acc)*, $x @ ..),
- $($rest)*
- )
- };
- // Variable length pattern without a binder
- (@make_pat; ($($acc:tt)*), .., $($rest:tt)*) => {
- $crate::match_vec!(@make_pat;
- ($($acc)*, ..),
- $($rest)*
- )
- };
- // Single item pattern
- (@make_pat; ($($acc:tt)*), $x:pat, $($rest:tt)*) => {
- $crate::match_vec!(@make_pat;
- ($($acc)*, $x),
- $($rest)*
- )
- };
- (@make_pat; (, $($acc:tt)*), $(,)*) => {
- [$($acc)*]
- };
- (@make_pat; ($($acc:tt)*), $(,)*) => {
- [$($acc)*]
- };
-
- (@make_filter; $x:ident @ .., $($rest:tt)*) => {
- $crate::match_vec!(@make_filter;
- $($rest)*
- )
- };
- (@make_filter; $variant:ident ($x:ident).., $($rest:tt)*) => {
- {
- // Circumvent https://github.com/rust-lang/rust/issues/59803
- let is_all_variant = || $x.iter()
- .all(|x| match x {
- $variant(_) => true,
- _ => false,
- });
- is_all_variant()
- }
- &&
- $crate::match_vec!(@make_filter;
- $($rest)*
- )
- };
- (@make_filter; .., $($rest:tt)*) => {
- $crate::match_vec!(@make_filter;
- $($rest)*
- )
- };
- (@make_filter; $x:pat, $($rest:tt)*) => {
- $crate::match_vec!(@make_filter;
- $($rest)*
- )
- };
- (@make_filter; $(,)*) => {
- true
- };
-
- ($arg:expr; $( [$($args:tt)*] => $body:expr ),* $(,)*) => {
- {
- let vec = $arg;
- // Match as references to decide which branch to take
- // I think `match_default_bindings` should make this always work but
- // there may be some patterns this doesn't capture.
- #[allow(unused_variables, unreachable_patterns)]
- match vec.as_slice() {
- $(
- $crate::match_vec!(@make_pat; (), $($args)*,)
- if
- $crate::match_vec!(@make_filter; $($args)*,)
- => {
- // Actually consume the values
- #[allow(unused_mut)]
- let mut iter = vec.into_iter();
- let ret =
- $crate::destructure_iter!(iter;
- [$($args)*] => $body
- );
- match ret {
- Some(x) => Ok(x),
- None => unreachable!(), // Hopefully
- }
- }
- )*
- _ => std::result::Result::Err(vec),
- }
- }
- };
-}
-
-#[test]
-fn test() {
- let test = |v: Vec<Option<isize>>| {
- match_vec!(v.into_iter();
- [Some(_x), None, None] => 4,
- [Some(_x), None] => 2,
- [None, Some(y)] => 1,
- [None, _y @ ..] => 3,
- [_x @ .., Some(y), Some(z), None] => y - z,
- [Some(ys)..] => ys.sum(),
- [] => 0,
- [..] => -1,
- )
- .unwrap()
- };
-
- assert_eq!(test(vec![Some(0), None, None]), 4);
- assert_eq!(test(vec![Some(0), None]), 2);
- assert_eq!(test(vec![None, Some(0)]), 1);
- assert_eq!(test(vec![Some(1), Some(2), Some(5), Some(14), None]), -9);
- assert_eq!(test(vec![Some(1), Some(2), Some(3), Some(4)]), 10);
- assert_eq!(test(vec![None]), 3);
- assert_eq!(test(vec![]), 0);
- assert_eq!(test(vec![Some(0), None, Some(1)]), -1);
-
- // Test move out of pattern
- #[derive(Debug)]
- struct Foo;
- let _: (Foo, Foo) = match_vec!(vec![Some(Foo), Some(Foo)];
- [Some(f1), Some(f2)] => (f1, f2),
- )
- .unwrap();
-
- // Test return ownership if no match
- let _: Vec<Foo> = match_vec!(vec![Foo];
- [] => "Error".to_string(),
- )
- .unwrap_err();
-}