Browse the implementors of #beVariable message and you will find other filters under BPatternVariableNode class, such as #beInstVar or #beLocalVar. If you miss something, just add a method. No new syntax required.
Finding these optimization opportunities can itself be a significant undertaking. It requires end-to-end understanding of the spec to identify which behaviors are observable and which can safely be elided. Even then, whether a given optimization is actually spec-compliant is often unclear. Implementers must make judgment calls about which semantics they can relax without breaking compatibility. This puts enormous pressure on runtime teams to become spec experts just to achieve acceptable performance.
。关于这个话题，夫子提供了深入分析
面对来自德国的外甥和镜头，大舅无所顾忌，他直言财产当年被掠夺。但他谈论战争本身甚少，弥漫于言谈间的，多是家庭创痛。
if (right < n) {
const format = (v) = JSON.stringify(v, null, 2);