walkBlock

fn walkBlock(
    w: *Walk,
    block_node: Ast.Node.Index,
    statements: []const Ast.Node.Index,
) Error!void

File

Code

fn walkBlock(
    w: *Walk,
    block_node: Ast.Node.Index,
    statements: []const Ast.Node.Index,
) Error!void {
    _ = block_node;
    const ast = w.ast;

    for (statements) |stmt| {
        switch (ast.nodeTag(stmt)) {
            .global_var_decl,
            .local_var_decl,
            .simple_var_decl,
            .aligned_var_decl,
            => {
                const var_decl = ast.fullVarDecl(stmt).?;
                if (var_decl.ast.init_node != .none and
                    isUndefinedIdent(w.ast, var_decl.ast.init_node.unwrap().?))
                {
                    try w.transformations.append(.{ .delete_var_decl = .{
                        .var_decl_node = stmt,
                        .references = .empty,
                    } });
                    const name_tok = var_decl.ast.mut_token + 1;
                    const name_bytes = ast.tokenSlice(name_tok);
                    try w.replace_names.put(w.gpa, name_bytes, @intCast(w.transformations.items.len - 1));
                } else {
                    try walkLocalVarDecl(w, var_decl);
                }
            },

            else => {
                switch (categorizeStmt(ast, stmt)) {
                    // Don't try to remove `_ = foo;` discards; those are handled separately.
                    .discard_identifier => {},
                    // definitely try to remove `_ = undefined;` though.
                    .discard_undefined, .trap_call, .other => {
                        try w.transformations.append(.{ .delete_node = stmt });
                    },
                }
                try walkExpression(w, stmt);
            },
        }
    }
}