From 42f1cff5c1471e6bc3988a9810c20b8bcc1c84dd Mon Sep 17 00:00:00 2001 From: Tim Foley Date: Mon, 30 Oct 2017 08:54:09 -0700 Subject: Support explicit `this` expressions This is the first step towards supporting traditional object-oriented method definitions; the second step will be to allow `this` expressions to be implicit. - Add a test case using explicit `this`, and expected output - Update parsing logic for expressions so that it handled identifiers similarly to the declaration and statement logic: first try to parse using a syntax declaration looked up in the curent scope, and otherwise fall back to the ordinary `VarExpr` case. * As long as I'm making that change: switch `true` and `false` to be parsed via the callback mechanism rather than be special-cased. * This change will also help out if we ever wanted to add `super`/`base` expressions, `new`, `sizeof`/`alignof` or any other expression keywords. - Add a `ThisExpr` node and register a parser callback for it. - Add semantic checks for `ThisExpr`: basically just look upwards through scopes until we find either an aggregate type declaration or an `extension` declaration, and then use that as the type of the expression. - TODO: eventually we need to guard against a `this` expression inside of a `static` member. - The IR generation logic already handled creation of `this` parameters in function signatures; the missing piece was to register the appropriate parameter in the context, so that we can use it as the lowering of a `this` expression. --- source/slang/emit.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'source/slang/emit.cpp') diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp index 6b411a25d..38e7376df 100644 --- a/source/slang/emit.cpp +++ b/source/slang/emit.cpp @@ -2381,6 +2381,17 @@ struct EmitVisitor if(needClose) Emit(")"); } + void visitThisExpr(ThisExpr* expr, ExprEmitArg const& arg) + { + auto prec = kEOp_Atomic; + auto outerPrec = arg.outerPrec; + bool needClose = MaybeEmitParens(outerPrec, prec); + + Emit("this"); + + if(needClose) Emit(")"); + } + void visitSwizzleExpr(SwizzleExpr* swizExpr, ExprEmitArg const& arg) { auto prec = kEOp_Postfix; -- cgit v1.2.3