我来自JS，所以不确定字符串字面量。
我有以下语法
[GMSServices provideAPIKey:@"ABCXYZ"];
if I remove @ from the above, swift throws the following error String literal must be prefixed by '@'
Can someone explain me why I am getting this error and what are string literals? This answer wasn't helpful in above context: What does the @ prefix do on string literals in C#
首先，不要在Internet上发布API密钥。我已经编辑了您的问题以删除密钥，但是它在问题历史记录中仍然可见。
Anyway, the code you quoted is Objective-C code, not Swift code. That code declares an
NSStringliteral.NSStringis an Objective-C class. In contrast to a plain C string, theNSStringclass provides many APIs for using and manipulating strings, and the Objective-C runtime managesNSStringmemory so you don't have to.在Swift中，等效代码为
Here, we are using a Swift
Stringliteral, which is similar toNSString, with many APIs and with automatic memory management, but we don't need an@prefix because Swift is not a superset of C.