Move built-in syntax extensions to a separate crate

src/libsyntax_ext/lib.rs

@@ -0,0 +1,82 @@
+// Copyright 2015 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.
+
+//! Syntax extensions in the Rust compiler.
+
+#![crate_name = "syntax_ext"]
+#![crate_type = "dylib"]
+#![crate_type = "rlib"]
+#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
+       html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
+       html_root_url = "https://doc.rust-lang.org/nightly/")]
+
+#![feature(rustc_private)]
+#![feature(str_char)]
+
+extern crate fmt_macros;
+extern crate syntax;
+
+use syntax::ext::base::{MacroExpanderFn, NormalTT};
+use syntax::ext::base::{SyntaxEnv, SyntaxExtension};
+use syntax::parse::token::intern;
+
+// A variant of 'try!' that panics on Err(FatalError). This is used as a
+// crutch on the way towards a non-panic!-prone parser. It should be used
+// for fatal parsing errors; eventually we plan to convert all code using
+// panictry to just use normal try
+macro_rules! panictry {
+    ($e:expr) => ({
+        use std::result::Result::{Ok, Err};
+        use syntax::diagnostic::FatalError;
+        match $e {
+            Ok(e) => e,
+            Err(FatalError) => panic!(FatalError)
+        }
+    })
+}
+
+mod asm;
+mod cfg;
+mod concat;
+mod concat_idents;
+mod deriving;
+mod env;
+mod format;
+mod log_syntax;
+mod trace_macros;
+
+pub fn register_builtins(env: &mut SyntaxEnv) {
+    // utility function to simplify creating NormalTT syntax extensions
+    fn builtin_normal_expander(f: MacroExpanderFn) -> SyntaxExtension {
+        NormalTT(Box::new(f), None, false)
+    }
+
+    env.insert(intern("asm"),
+               builtin_normal_expander(asm::expand_asm));
+    env.insert(intern("cfg"),
+               builtin_normal_expander(cfg::expand_cfg));
+    env.insert(intern("concat"),
+               builtin_normal_expander(concat::expand_syntax_ext));
+    env.insert(intern("concat_idents"),
+               builtin_normal_expander(concat_idents::expand_syntax_ext));
+    env.insert(intern("env"),
+               builtin_normal_expander(env::expand_env));
+    env.insert(intern("option_env"),
+               builtin_normal_expander(env::expand_option_env));
+    env.insert(intern("format_args"),
+               // format_args uses `unstable` things internally.
+               NormalTT(Box::new(format::expand_format_args), None, true));
+    env.insert(intern("log_syntax"),
+               builtin_normal_expander(log_syntax::expand_syntax_ext));
+    env.insert(intern("trace_macros"),
+               builtin_normal_expander(trace_macros::expand_trace_macros));
+
+    deriving::register_all(env);
+}