Multiple function calls in one line I'm translating a small java library to objective c. I'm having some trouble translating the following:
return other.tokens[0].equals(tokens[0]) &&
       other.tokens[1].equals(tokens[1]) &&
       other.tokens[2].equals(tokens[2]) &&
       other.tokens[3].equals(tokens[3]);

where other is an instance of a class, and tokens is a string array that is an instance variable of the same class. So far, what I have is this:
return ([other [[tokens[0] equals:tokens[0]]]] && 
[other [[tokens[1] equals:tokens[1]]]] && 
[other [[tokens[2] equals:tokens[2]]]] && 
[other [[tokens[3] equals:tokens[3]]]]);

But I keep getting an "expected identifier" error, which I believe means I have something wrong with my syntax. 

since you have getToken method implementation in Quad class, you can use it with following implementation.
return ([[other getTokens:0] isEqualToString: [self getTokens[0]] &&
       [[other getTokens:1] isEqualToString: [self getTokens[1]] &&
       [[other getTokens:2] isEqualToString: [self getTokens[2]] &&
       [[other getTokens:3] isEqualToString: [self getTokens[3]]);


You can make your life easy be breaking four conditions into 4 lines as:  
BOOL b1=[other.tokens[0] isEqualTo:tokens[0]];
BOOL b2=[other.tokens[1] isEqualTo:tokens[1]];
BOOL b3=[other.tokens[2] isEqualTo:tokens[2]];
BOOL b4=[other.tokens[3] isEqualTo:tokens[3]];

return (b1 && b2 && b3 && b4);

Also, alternate way is iterate through all the values, if any one is False return NO:
for(NSInteger i=0; i<4; i++){
    if(![other.tokens[i] isEqualTo:tokens[i]]){
return NO;
    }
}
return YES;

And read this, as I am not sure what kind of value are you comparing (Object / NSString / Number etc).. Implementing -hash / -isEqual: / -isEqualTo...: for Objective-C collections

There is no such method "equals" in Objective C. If you are working on string comparison, it should be 
[[token objectAtIndex: 0] isEqualToString:[token objectAtIndex: 0]] 

but why you are comparing same strings.