意外的情况，编译时预期表达式错误

Question

When I compile the following code, it generates

*syntax error: unexpected case, expecting expression* at line *case workerAddr = <- mr.registerChannel:*

I do not know why it happens since I just want to workerAddr to be set by either channel. Any suggestion will be appreciated.

for i:= 0; i < mr.nMap; i++ {   
    go func(jobCount) {
        for {
            var workerAddr string
            Select {
                // get a worker either from registerChannel or from idle channel
                case workerAddr = <- mr.registerChannel:
                case workerAddr = <- mr.idleChannel:
            } 
            // omit the following code
        }
    }(i)
}

Answer 1

It happens because you have written Select when you should have written select.

None of the Go keywords are capitalized, so when the compiler sees a capitalized word, it knows immediately that it's not an expression, and therefore a syntax error.