JavaScript字节码编译器？(JavaScript bytecode compiler?)
对于我正在进行的项目，我需要一种方法将JavaScript编译成一些中间语言或字节码，以便我可以单步执行它。 我知道现代浏览器中的许多JavaScript引擎都是这样做的，但它们并不能使得生成的字节码可访问。 这种JavaScript编译有一个很好的现成工具吗？
For a project I'm tangentially working on, I need a way to compile JavaScript into some intermediate language or bytecode so that I can single-step through it. I know that many of the JavaScript engines in modern browsers do something like this, but they don't make the resulting bytecode accessible. Is there a good off-the-shelf tool for this sort of JavaScript compilation?
原文：https://stackoverflow.com/questions/5356786
更新时间：2023-08-12 12:08
最满意答案
保持原样。 使用coalesce将阻止查询计划程序正确地执行其工作，并且您将最终得到糟糕的查询计划。
最好我知道，以下表达式将使用btree索引：
col = 'val'col is null以下表达式不会使用btree索引：
col is [not] 'val'(col = 'val') is [not] <true | false | null>col is [not] distinct from 'val'coalesce(col, 'val') = 'val'coalesce(col = 'val', <true | false | null>)Keep it the way it is. Using coalesce will prevent the query planner from doing its job properly, and you'll end up with sucky query plans.
Best I'm aware, the following expressions will use a btree index:
col = 'val'col is nullThe following expressions will not use a btree index:
col is [not] 'val'(col = 'val') is [not] <true | false | null>col is [not] distinct from 'val'coalesce(col, 'val') = 'val'coalesce(col = 'val', <true | false | null>)
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保持原样。 使用coalesce将阻止查询计划程序正确地执行其工作，并且您将最终得到糟糕的查询计划。 最好我知道，以下表达式将使用btree索引： col = 'val' col is null 以下表达式不会使用btree索引： col is [not] 'val' (col = 'val') is [not]
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