auto merge of #5120 : jbclements/rust/macros-have-scope, r=pcwalton

r?

After this patch, macros declared in a module, function, or block can only be used inside of that module, function or block, with the exception of modules declared with the #[macro_escape] attribute; these modules allow macros to escape, and can be used as a limited macro export mechanism.

This pull request also includes miscellaneous comments, lots of new test cases, a few renamings, and a few as-yet-unused data definitions for hygiene.

Author: bors

src/libcore/hash.rs

@@ -186,42 +186,46 @@ fn SipState(key0: u64, key1: u64) -> SipState {
     state
 }
 
+// sadly, these macro definitions can't appear later,
+// because they're needed in the following defs;
+// this design could be improved.
+
+macro_rules! u8to64_le (
+    ($buf:expr, $i:expr) =>
+    ($buf[0+$i] as u64 |
+     $buf[1+$i] as u64 << 8 |
+     $buf[2+$i] as u64 << 16 |
+     $buf[3+$i] as u64 << 24 |
+     $buf[4+$i] as u64 << 32 |
+     $buf[5+$i] as u64 << 40 |
+     $buf[6+$i] as u64 << 48 |
+     $buf[7+$i] as u64 << 56)
+)
+
+macro_rules! rotl (
+    ($x:expr, $b:expr) =>
+    (($x << $b) | ($x >> (64 - $b)))
+)
+
+macro_rules! compress (
+    ($v0:expr, $v1:expr, $v2:expr, $v3:expr) =>
+    ({
+        $v0 += $v1; $v1 = rotl!($v1, 13); $v1 ^= $v0;
+        $v0 = rotl!($v0, 32);
+        $v2 += $v3; $v3 = rotl!($v3, 16); $v3 ^= $v2;
+        $v0 += $v3; $v3 = rotl!($v3, 21); $v3 ^= $v0;
+        $v2 += $v1; $v1 = rotl!($v1, 17); $v1 ^= $v2;
+        $v2 = rotl!($v2, 32);
+    })
+)
+
 
 impl io::Writer for SipState {
 
     // Methods for io::writer
     #[inline(always)]
     fn write(&self, msg: &[const u8]) {
 
-        macro_rules! u8to64_le (
-            ($buf:expr, $i:expr) =>
-            ($buf[0+$i] as u64 |
-             $buf[1+$i] as u64 << 8 |
-             $buf[2+$i] as u64 << 16 |
-             $buf[3+$i] as u64 << 24 |
-             $buf[4+$i] as u64 << 32 |
-             $buf[5+$i] as u64 << 40 |
-             $buf[6+$i] as u64 << 48 |
-             $buf[7+$i] as u64 << 56)
-        );
-
-        macro_rules! rotl (
-            ($x:expr, $b:expr) =>
-            (($x << $b) | ($x >> (64 - $b)))
-        );
-
-        macro_rules! compress (
-            ($v0:expr, $v1:expr, $v2:expr, $v3:expr) =>
-            ({
-                $v0 += $v1; $v1 = rotl!($v1, 13); $v1 ^= $v0;
-                $v0 = rotl!($v0, 32);
-                $v2 += $v3; $v3 = rotl!($v3, 16); $v3 ^= $v2;
-                $v0 += $v3; $v3 = rotl!($v3, 21); $v3 ^= $v0;
-                $v2 += $v1; $v1 = rotl!($v1, 17); $v1 ^= $v2;
-                $v2 = rotl!($v2, 32);
-            })
-        );
-
         let length = msg.len();
         self.length += length;
 

src/librustc/middle/trans/_match.rs

@@ -172,11 +172,6 @@ use syntax::ast_util;
 use syntax::codemap::span;
 use syntax::print::pprust::pat_to_str;
 
-pub fn macros() {
-    // FIXME(#3114): Macro import/export.
-    include!("macros.rs");
-}
-
 // An option identifying a literal: either a unit-like struct or an
 // expression.
 pub enum Lit {

src/librustc/middle/trans/controlflow.rs

@@ -18,11 +18,6 @@ use middle::trans::datum::*;
 
 use core::str;
 
-pub fn macros() {
-    // FIXME(#3114): Macro import/export.
-    include!("macros.rs");
-}
-
 pub fn trans_block(bcx: block, b: &ast::blk, dest: expr::Dest) -> block {
     let _icx = bcx.insn_ctxt("trans_block");
     let mut bcx = bcx;

src/librustc/middle/trans/expr.rs

@@ -149,8 +149,6 @@ use syntax::codemap::spanned;
 // These are passed around by the code generating functions to track the
 // destination of a computation's value.
 
-fn macros() { include!("macros.rs"); } // FIXME(#3114): Macro import/export.
-
 pub enum Dest {
     SaveIn(ValueRef),
     Ignore,

src/librustc/middle/trans/macros.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-{
+#[macro_escape];
 
 macro_rules! unpack_datum(
     ($bcx: ident, $inp: expr) => (
@@ -18,7 +18,7 @@ macro_rules! unpack_datum(
             db.datum
         }
     )
-);
+)
 
 macro_rules! unpack_result(
     ($bcx: ident, $inp: expr) => (
@@ -28,7 +28,7 @@ macro_rules! unpack_result(
             db.val
         }
     )
-);
+)
 
 macro_rules! trace_span(
     ($bcx: ident, $sp: expr, $str: expr) => (
@@ -39,7 +39,7 @@ macro_rules! trace_span(
             }
         }
     )
-);
+)
 
 macro_rules! trace(
     ($bcx: ident, $str: expr) => (
@@ -50,6 +50,5 @@ macro_rules! trace(
             }
         }
     )
-);
+)
 
-}

src/librustc/middle/trans/meth.rs

@@ -39,11 +39,6 @@ use syntax::ast_util::local_def;
 use syntax::print::pprust::expr_to_str;
 use syntax::{ast, ast_map};
 
-pub fn macros() {
-    // FIXME(#3114): Macro import/export.
-    include!("macros.rs");
-}
-
 /**
 The main "translation" pass for methods.  Generates code
 for non-monomorphized methods only.  Other methods will

src/librustc/middle/typeck/infer/combine.rs

@@ -72,11 +72,6 @@ use syntax::ast::{Onceness, purity, ret_style};
 use syntax::ast;
 use syntax::codemap::span;
 
-pub fn macros() {
-    // FIXME(#3114): Macro import/export.
-    include!("macros.rs");
-}
-
 pub trait Combine {
     fn infcx(&self) -> @mut InferCtxt;
     fn tag(&self) -> ~str;

src/librustc/middle/typeck/infer/lub.rs

@@ -24,11 +24,6 @@ use std::list;
 use syntax::ast::{Many, Once, extern_fn, m_const, impure_fn, noreturn};
 use syntax::ast::{pure_fn, ret_style, return_val, unsafe_fn};
 
-pub fn macros() {
-    // FIXME(#3114): Macro import/export.
-    include!("macros.rs");
-}
-
 pub enum Lub = CombineFields;  // least-upper-bound: common supertype
 
 pub impl Lub {

src/librustc/middle/typeck/infer/macros.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-{
+#[macro_escape];
 
 macro_rules! if_ok(
     ($inp: expr) => (
@@ -17,6 +17,5 @@ macro_rules! if_ok(
             Err(e) => { return Err(e); }
         }
     )
-);
+)
 
-}

src/librustc/middle/typeck/infer/mod.rs

@@ -287,6 +287,7 @@ use syntax::codemap;
 use syntax::ast_util;
 use syntax::codemap::span;
 
+pub mod macros;
 pub mod combine;
 pub mod glb;
 pub mod lattice;