Add pattern types to parser

Author: oli-obk

core/src/lib.rs

@@ -396,6 +396,9 @@ pub mod net;
 pub mod option;
 pub mod panic;
 pub mod panicking;
+#[cfg(not(bootstrap))]
+#[unstable(feature = "core_pattern_types", issue = "none")]
+pub mod pat;
 pub mod pin;
 pub mod result;
 pub mod sync;

core/src/pat.rs

@@ -0,0 +1,14 @@
+//! Helper module for exporting the `pattern_type` macro
+
+/// Creates a pattern type.
+/// ```ignore (cannot test this from within core yet)
+/// type Positive = std::pat::pattern_type!(i32 is 1..);
+/// ```
+#[macro_export]
+#[rustc_builtin_macro(pattern_type)]
+#[unstable(feature = "core_pattern_type", issue = "none")]
+macro_rules! pattern_type {
+    ($($arg:tt)*) => {
+        /* compiler built-in */
+    };
+}

std/src/lib.rs

@@ -576,6 +576,9 @@ pub mod net;
 pub mod num;
 pub mod os;
 pub mod panic;
+#[cfg(not(bootstrap))]
+#[unstable(feature = "core_pattern_types", issue = "none")]
+pub mod pat;
 pub mod path;
 pub mod process;
 pub mod sync;

std/src/pat.rs

@@ -0,0 +1,3 @@
+//! Helper module for exporting the `pattern_type` macro
+
+pub use core::pattern_type;