New Zig formal grammar (#1685)

Reverted #1628 and changed the grammar+parser of the language to not allow certain expr where types are expected

Author: Hejsil

build.zig

@@ -17,7 +17,7 @@ pub fn build(b: *Builder) !void {
 
     const rel_zig_exe = try os.path.relative(b.allocator, b.build_root, b.zig_exe);
     const langref_out_path = os.path.join(b.allocator, b.cache_root, "langref.html") catch unreachable;
-    var docgen_cmd = b.addCommand(null, b.env_map, [][]const u8.{
+    var docgen_cmd = b.addCommand(null, b.env_map, [][]const u8{
         docgen_exe.getOutputPath(),
         rel_zig_exe,
         "doc" ++ os.path.sep_str ++ "langref.html.in",
@@ -31,12 +31,12 @@ pub fn build(b: *Builder) !void {
     const test_step = b.step("test", "Run all the tests");
 
     // find the stage0 build artifacts because we're going to re-use config.h and zig_cpp library
-    const build_info = try b.exec([][]const u8.{
+    const build_info = try b.exec([][]const u8{
         b.zig_exe,
         "BUILD_INFO",
     });
     var index: usize = 0;
-    var ctx = Context.{
+    var ctx = Context{
         .cmake_binary_dir = nextValue(&index, build_info),
         .cxx_compiler = nextValue(&index, build_info),
         .llvm_config_exe = nextValue(&index, build_info),
@@ -162,7 +162,7 @@ fn addCppLib(b: *Builder, lib_exe_obj: var, cmake_binary_dir: []const u8, lib_na
     lib_exe_obj.addObjectFile(os.path.join(b.allocator, cmake_binary_dir, "zig_cpp", b.fmt("{}{}{}", lib_prefix, lib_name, lib_exe_obj.target.libFileExt())) catch unreachable);
 }
 
-const LibraryDep = struct.{
+const LibraryDep = struct {
     prefix: []const u8,
     libdirs: ArrayList([]const u8),
     libs: ArrayList([]const u8),
@@ -171,24 +171,24 @@ const LibraryDep = struct.{
 };
 
 fn findLLVM(b: *Builder, llvm_config_exe: []const u8) !LibraryDep {
-    const shared_mode = try b.exec([][]const u8.{ llvm_config_exe, "--shared-mode" });
+    const shared_mode = try b.exec([][]const u8{ llvm_config_exe, "--shared-mode" });
     const is_static = mem.startsWith(u8, shared_mode, "static");
     const libs_output = if (is_static)
-        try b.exec([][]const u8.{
+        try b.exec([][]const u8{
             llvm_config_exe,
             "--libfiles",
             "--system-libs",
         })
     else
-        try b.exec([][]const u8.{
+        try b.exec([][]const u8{
             llvm_config_exe,
             "--libs",
         });
-    const includes_output = try b.exec([][]const u8.{ llvm_config_exe, "--includedir" });
-    const libdir_output = try b.exec([][]const u8.{ llvm_config_exe, "--libdir" });
-    const prefix_output = try b.exec([][]const u8.{ llvm_config_exe, "--prefix" });
+    const includes_output = try b.exec([][]const u8{ llvm_config_exe, "--includedir" });
+    const libdir_output = try b.exec([][]const u8{ llvm_config_exe, "--libdir" });
+    const prefix_output = try b.exec([][]const u8{ llvm_config_exe, "--prefix" });
 
-    var result = LibraryDep.{
+    var result = LibraryDep{
         .prefix = mem.split(prefix_output, " \r\n").next().?,
         .libs = ArrayList([]const u8).init(b.allocator),
         .system_libs = ArrayList([]const u8).init(b.allocator),
@@ -328,7 +328,7 @@ fn addCxxKnownPath(
     objname: []const u8,
     errtxt: ?[]const u8,
 ) !void {
-    const path_padded = try b.exec([][]const u8.{
+    const path_padded = try b.exec([][]const u8{
         ctx.cxx_compiler,
         b.fmt("-print-file-name={}", objname),
     });
@@ -344,7 +344,7 @@ fn addCxxKnownPath(
     exe.addObjectFile(path_unpadded);
 }
 
-const Context = struct.{
+const Context = struct {
     cmake_binary_dir: []const u8,
     cxx_compiler: []const u8,
     llvm_config_exe: []const u8,