Move macro_rules! macros to libstd

sfackler · nathanielherman · commit 15e7a7d82748 · 2014-01-30T16:58:45.000-05:00
They all have to go into a single module at the moment unfortunately. Ideally, the logging macros would live in std::logging, condition! would live in std::condition, format! in std::fmt, etc. However, this introduces cyclic dependencies between those modules and the macros they use which the current expansion system can't deal with. We may be able to get around this by changing the expansion phase to a two-pass system but that's for a later PR. Closes rust-lang#2247 cc rust-lang#11763
diff --git a/src/librustc/driver/driver.rs b/src/librustc/driver/driver.rs
@@ -176,17 +176,16 @@ pub fn phase_2_configure_and_expand(sess: Session,
     time(time_passes, "gated feature checking", (), |_|
          front::feature_gate::check_crate(sess, &crate));
 
+    crate = time(time_passes, "crate injection", crate, |crate|
+                 front::std_inject::maybe_inject_crates_ref(sess, crate));
+
     // strip before expansion to allow macros to depend on
     // configuration variables e.g/ in
     //
     //   #[macro_escape] #[cfg(foo)]
     //   mod bar { macro_rules! baz!(() => {{}}) }
     //
     // baz! should not use this definition unless foo is enabled.
-    crate = time(time_passes, "std macros injection", crate, |crate|
-                 syntax::ext::expand::inject_std_macros(sess.parse_sess,
-                                                        cfg.clone(),
-                                                        crate));
 
     crate = time(time_passes, "configuration 1", crate, |crate|
                  front::config::strip_unconfigured_items(crate));
@@ -207,8 +206,8 @@ pub fn phase_2_configure_and_expand(sess: Session,
     crate = time(time_passes, "maybe building test harness", crate, |crate|
                  front::test::modify_for_testing(sess, crate));
 
-    crate = time(time_passes, "std injection", crate, |crate|
-                 front::std_inject::maybe_inject_libstd_ref(sess, crate));
+    crate = time(time_passes, "prelude injection", crate, |crate|
+                 front::std_inject::maybe_inject_prelude(sess, crate));
 
     time(time_passes, "assinging node ids and indexing ast", crate, |crate|
          front::assign_node_ids_and_map::assign_node_ids_and_map(sess, crate))
diff --git a/src/librustc/front/std_inject.rs b/src/librustc/front/std_inject.rs
@@ -23,10 +23,18 @@ use syntax::util::small_vector::SmallVector;
 
 pub static VERSION: &'static str = "0.10-pre";
 
-pub fn maybe_inject_libstd_ref(sess: Session, crate: ast::Crate)
+pub fn maybe_inject_crates_ref(sess: Session, crate: ast::Crate)
                                -> ast::Crate {
     if use_std(&crate) {
-        inject_libstd_ref(sess, crate)
+        inject_crates_ref(sess, crate)
+    } else {
+        crate
+    }
+}
+
+pub fn maybe_inject_prelude(sess: Session, crate: ast::Crate) -> ast::Crate {
+    if use_std(&crate) {
+        inject_prelude(sess, crate)
     } else {
         crate
     }
@@ -44,13 +52,6 @@ fn no_prelude(attrs: &[ast::Attribute]) -> bool {
     attr::contains_name(attrs, "no_implicit_prelude")
 }
 
-fn spanned<T>(x: T) -> codemap::Spanned<T> {
-    codemap::Spanned {
-        node: x,
-        span: DUMMY_SP,
-    }
-}
-
 struct StandardLibraryInjector {
     sess: Session,
 }
@@ -71,7 +72,11 @@ impl fold::Folder for StandardLibraryInjector {
             node: ast::ViewItemExternMod(self.sess.ident_of("std"),
                                          with_version("std"),
                                          ast::DUMMY_NODE_ID),
-            attrs: ~[],
+            attrs: ~[
+                attr::mk_attr(attr::mk_list_item(@"phase",
+                                                 ~[attr::mk_word_item(@"syntax"),
+                                                   attr::mk_word_item(@"link")]))
+            ],
             vis: ast::Inherited,
             span: DUMMY_SP
         }];
@@ -96,22 +101,43 @@ impl fold::Folder for StandardLibraryInjector {
         }
 
         vis.push_all(crate.module.view_items);
-        let mut new_module = ast::Mod {
+        let new_module = ast::Mod {
             view_items: vis,
             ..crate.module.clone()
         };
 
-        if !no_prelude(crate.attrs) {
-            // only add `use std::prelude::*;` if there wasn't a
-            // `#[no_implicit_prelude];` at the crate level.
-            new_module = self.fold_mod(&new_module);
-        }
-
         ast::Crate {
             module: new_module,
             ..crate
         }
     }
+}
+
+fn inject_crates_ref(sess: Session, crate: ast::Crate) -> ast::Crate {
+    let mut fold = StandardLibraryInjector {
+        sess: sess,
+    };
+    fold.fold_crate(crate)
+}
+
+struct PreludeInjector {
+    sess: Session,
+}
+
+
+impl fold::Folder for PreludeInjector {
+    fn fold_crate(&mut self, crate: ast::Crate) -> ast::Crate {
+        if !no_prelude(crate.attrs) {
+            // only add `use std::prelude::*;` if there wasn't a
+            // `#[no_implicit_prelude];` at the crate level.
+            ast::Crate {
+                module: self.fold_mod(&crate.module),
+                ..crate
+            }
+        } else {
+            crate
+        }
+    }
 
     fn fold_item(&mut self, item: @ast::Item) -> SmallVector<@ast::Item> {
         if !no_prelude(item.attrs) {
@@ -142,7 +168,7 @@ impl fold::Folder for StandardLibraryInjector {
             ],
         };
 
-        let vp = @spanned(ast::ViewPathGlob(prelude_path, ast::DUMMY_NODE_ID));
+        let vp = @codemap::dummy_spanned(ast::ViewPathGlob(prelude_path, ast::DUMMY_NODE_ID));
         let vi2 = ast::ViewItem {
             node: ast::ViewItemUse(~[vp]),
             attrs: ~[],
@@ -161,8 +187,8 @@ impl fold::Folder for StandardLibraryInjector {
     }
 }
 
-fn inject_libstd_ref(sess: Session, crate: ast::Crate) -> ast::Crate {
-    let mut fold = StandardLibraryInjector {
+fn inject_prelude(sess: Session, crate: ast::Crate) -> ast::Crate {
+    let mut fold = PreludeInjector {
         sess: sess,
     };
     fold.fold_crate(crate)
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
@@ -1,4 +1,4 @@
-// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -76,6 +76,8 @@
 #[cfg(test)] pub use ops = realstd::ops;
 #[cfg(test)] pub use cmp = realstd::cmp;
 
+mod macros;
+
 mod rtdeps;
 
 /* The Prelude. */
diff --git a/src/libstd/macros.rs b/src/libstd/macros.rs
@@ -0,0 +1,192 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+#[macro_escape];
+
+#[macro_export]
+macro_rules! ignore (($($x:tt)*) => (()))
+
+#[macro_export]
+macro_rules! log(
+    ($lvl:expr, $($arg:tt)+) => ({
+        let lvl = $lvl;
+        if lvl <= __log_level() {
+            format_args!(|args| {
+                ::std::logging::log(lvl, args)
+            }, $($arg)+)
+        }
+    })
+)
+#[macro_export]
+macro_rules! error( ($($arg:tt)*) => (log!(1u32, $($arg)*)) )
+#[macro_export]
+macro_rules! warn ( ($($arg:tt)*) => (log!(2u32, $($arg)*)) )
+#[macro_export]
+macro_rules! info ( ($($arg:tt)*) => (log!(3u32, $($arg)*)) )
+#[macro_export]
+macro_rules! debug( ($($arg:tt)*) => (
+    if cfg!(not(ndebug)) { log!(4u32, $($arg)*) }
+))
+
+#[macro_export]
+macro_rules! log_enabled(
+    ($lvl:expr) => ( {
+        let lvl = $lvl;
+        lvl <= __log_level() && (lvl != 4 || cfg!(not(ndebug)))
+    } )
+)
+
+#[macro_export]
+macro_rules! fail(
+    () => (
+        fail!("explicit failure")
+    );
+    ($msg:expr) => (
+        ::std::rt::begin_unwind($msg, file!(), line!())
+    );
+    ($fmt:expr, $($arg:tt)*) => (
+        ::std::rt::begin_unwind(format!($fmt, $($arg)*), file!(), line!())
+    )
+)
+
+#[macro_export]
+macro_rules! assert(
+    ($cond:expr) => {
+        if !$cond {
+            fail!("assertion failed: {:s}", stringify!($cond))
+        }
+    };
+    ($cond:expr, $msg:expr) => {
+        if !$cond {
+            fail!($msg)
+        }
+    };
+    ($cond:expr, $( $arg:expr ),+) => {
+        if !$cond {
+            fail!( $($arg),+ )
+        }
+    }
+)
+
+#[macro_export]
+macro_rules! assert_eq (
+    ($given:expr , $expected:expr) => (
+        {
+            let given_val = &($given);
+            let expected_val = &($expected);
+            // check both directions of equality....
+            if !((*given_val == *expected_val) &&
+                 (*expected_val == *given_val)) {
+                fail!("assertion failed: `(left == right) && (right == left)` \
+                       (left: `{:?}`, right: `{:?}`)", *given_val, *expected_val)
+            }
+        }
+    )
+)
+
+/// A utility macro for indicating unreachable code. It will fail if
+/// executed. This is occasionally useful to put after loops that never
+/// terminate normally, but instead directly return from a function.
+///
+/// # Example
+///
+/// ```rust
+/// fn choose_weighted_item(v: &[Item]) -> Item {
+///     assert!(!v.is_empty());
+///     let mut so_far = 0u;
+///     for item in v.iter() {
+///         so_far += item.weight;
+///         if so_far > 100 {
+///             return item;
+///         }
+///     }
+///     // The above loop always returns, so we must hint to the
+///     // type checker that it isn't possible to get down here
+///     unreachable!();
+/// }
+/// ```
+#[macro_export]
+macro_rules! unreachable (() => (
+    fail!("internal error: entered unreachable code");
+))
+
+#[macro_export]
+macro_rules! condition (
+
+    { pub $c:ident: $input:ty -> $out:ty; } => {
+
+        pub mod $c {
+            #[allow(unused_imports)];
+            #[allow(non_uppercase_statics)];
+            #[allow(missing_doc)];
+
+            use super::*;
+
+            local_data_key!(key: @::std::condition::Handler<$input, $out>)
+
+            pub static cond :
+                ::std::condition::Condition<$input,$out> =
+                ::std::condition::Condition {
+                    name: stringify!($c),
+                    key: key
+                };
+        }
+    };
+
+    { $c:ident: $input:ty -> $out:ty; } => {
+
+        mod $c {
+            #[allow(unused_imports)];
+            #[allow(non_uppercase_statics)];
+            #[allow(dead_code)];
+
+            use super::*;
+
+            local_data_key!(key: @::std::condition::Handler<$input, $out>)
+
+            pub static cond :
+                ::std::condition::Condition<$input,$out> =
+                ::std::condition::Condition {
+                    name: stringify!($c),
+                    key: key
+                };
+        }
+    }
+)
+
+#[macro_export]
+macro_rules! format(($($arg:tt)*) => (
+    format_args!(::std::fmt::format, $($arg)*)
+))
+#[macro_export]
+macro_rules! write(($dst:expr, $($arg:tt)*) => (
+    format_args!(|args| { ::std::fmt::write($dst, args) }, $($arg)*)
+))
+#[macro_export]
+macro_rules! writeln(($dst:expr, $($arg:tt)*) => (
+    format_args!(|args| { ::std::fmt::writeln($dst, args) }, $($arg)*)
+))
+#[macro_export]
+macro_rules! print (
+    ($($arg:tt)*) => (format_args!(::std::io::stdio::print_args, $($arg)*))
+)
+#[macro_export]
+macro_rules! println (
+    ($($arg:tt)*) => (format_args!(::std::io::stdio::println_args, $($arg)*))
+)
+
+#[macro_export]
+macro_rules! local_data_key (
+    ($name:ident: $ty:ty) => (
+        static $name: ::std::local_data::Key<$ty> = &::std::local_data::Key;
+    );
+    (pub $name:ident: $ty:ty) => (
+        pub static $name: ::std::local_data::Key<$ty> = &::std::local_data::Key;
+    )
+)
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
diff --git a/src/test/compile-fail/tag-that-dare-not-speak-its-name.rs b/src/test/compile-fail/tag-that-dare-not-speak-its-name.rs
