diff options
Diffstat (limited to 'src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md')
-rw-r--r-- | src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md | 41 |
1 files changed, 2 insertions, 39 deletions
diff --git a/src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md b/src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md index 5b495b4fe..d058a5838 100644 --- a/src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md +++ b/src/doc/rustc-dev-guide/src/rustc-driver-interacting-with-the-ast.md @@ -5,45 +5,8 @@ ## Getting the type of an expression To get the type of an expression, use the `global_ctxt` to get a `TyCtxt`. -The following was tested with <!-- date-check: Jan 2023 --> `nightly-2022-12-19` -(see [here][example] for the complete example): - -[example]: https://github.com/rust-lang/rustc-dev-guide/blob/master/examples/rustc-driver-interacting-with-the-ast.rs +The following was tested with <!-- date-check: Feb 2023 --> `nightly-2023-02-13`: ```rust -let config = rustc_interface::Config { - input: config::Input::Str { - name: source_map::FileName::Custom("main.rs".to_string()), - input: "fn main() { let message = \"Hello, world!\"; println!(\"{}\", message); }" - .to_string(), - }, - /* other config */ -}; -rustc_interface::run_compiler(config, |compiler| { - compiler.enter(|queries| { - // Analyze the crate and inspect the types under the cursor. - queries.global_ctxt().unwrap().take().enter(|tcx| { - // Every compilation contains a single crate. - let hir_krate = tcx.hir(); - // Iterate over the top-level items in the crate, looking for the main function. - for id in hir_krate.items() { - let item = hir_krate.item(id); - // Use pattern-matching to find a specific node inside the main function. - if let rustc_hir::ItemKind::Fn(_, _, body_id) = item.kind { - let expr = &tcx.hir().body(body_id).value; - if let rustc_hir::ExprKind::Block(block, _) = expr.kind { - if let rustc_hir::StmtKind::Local(local) = block.stmts[0].kind { - if let Some(expr) = local.init { - let hir_id = expr.hir_id; // hir_id identifies the string "Hello, world!" - let def_id = tcx.hir().local_def_id(item.hir_id()); // def_id identifies the main function - let ty = tcx.typeck(def_id).node_type(hir_id); - println!("{:?}: {:?}", expr, ty); - } - } - } - } - } - }) - }); -}); +{{#include ../examples/rustc-driver-interacting-with-the-ast.rs}} ``` |