javascript - reactjs 源代码中明显的 ifs 有什么意义？

Question

我发现源码里满是对比if ("production"!== "development")。

例如(来自 https://cdnjs.cloudflare.com/ajax/libs/react/0.12.2/react.js ，第 6240 行):

if ("production" !== "development") {
    this._checkPropTypes(
        contextTypes,
        maskedContext,
        ReactPropTypeLocations.context
    );
}

但是为什么？此类检查的结果始终相同。

Answer 1

他们使用 browserify与 envify .

envify will replace your environment variable checks with ordinary strings - only the variables you use will be included, so you don't have to worry about, say, AWS_SECRET_KEY leaking through either. [...] By running this through a good minifier (e.g. UglifyJS2), the above code would be stripped out completely.