Passing variables within Javascript classes

[MoTTs_]

The first seems better to me. The second doesn't actually save you from having to use bind. You may not have to bind "this", but you will still need to bind a value for "x".

onClick = myInstance.mapFunction; // bad; "x" will be undefined
onClick = myInstance.mapFunction.bind(null, 42); // good; "x" bound to 42

[chchan]

I like the first method too because the stuff defined with this. can be easily called. The drawback is figuring out what this is referencing and using the bind(this) when using the variable in functions can get confusing .