This is using some idiomatic JavaScript : the double negation. 这里用到了一些符合语言习惯的JavaScript:双重否定(DN)。
The double negation technique is used again, but this time you're checking for an object called geolocation that should be a property of the navigator object. 这里再次使用了双重否定(DN),但这次您要检测一个名为geolocation的对象,它应该是navigator对象的一个属性。
Putting a single negation in front of it will evaluate to true, thus a double negation will evaluate to false. 如果在它前面放上一个单否定,就会被求值为真,因此放上一个双否定将被求值为假。
This paper, attempts a psycholinguistic case study of the thinking process of three subjects in the given task of translating English sentences of double negation into Chinese. 从心理语言学角度切入,运用心理学口语报告法对三名被试的英语双重否定(DN)句汉译过程进行了个案研究,具体考察了思维过程中元认知和认知策略的应用情况。
This paper discusses some special negative structures in English, such as transferred negation, double negation, implied negation, partial negation and entire negation. 本文探讨英语语言中一些特殊的否定结构,如转移否定、双重否定(DN)、隐形否定、部分否定和全体否定等。