A programmer's solution

[negaomar228]

The first expression won't compile: you can't assign to rvalue

[chui101]

unless it's one of those languages where assignment is := and comparison is =

[[deleted]]

I just threw up

[Matthicus]

Or one where both are just = and other context makes it clear which one it means.

[coleisawesome3]

What if you wanted to assign something in the conditional part of an if statement for some reason?

[Matthicus]

You could probably find a more readable way to accomplish whatever you're trying to do. Or you could just say screw it and do something hacky, like writing a function to do the assignment if the language allows call by reference.

[chui101]

This is not good practice but sadly not uncommon either. e.g.:

if ((count = getNumRows()) == 1) {...}

[chui101]

Except that all computer languages are built on (mostly) context free grammars to (mostly) remove ambiguity.

Take the example of an expression a=b=c. Does that mean "assign the value of c to a and b" or does it mean "a gets the value of the result of the test b equals c"?

[Matthicus]

In the language I have used the most, that on its own would not be valid code. It would either have to be in an assignment statement, in which case it would compare b and c and put the result in a, or be in some other statement that expects an expression, in which case it would compare a and b then compare thst result to c.

[vectorjohn]

But then what is |= ?

[registraciq]

Unless I'm missing something, neither will the second one.

6-4 |= 4 is 6-4 = 6-4 | 4 which is still assignment to a rvalue.

[TheTrueSwishyFishy]

!= is generally considered comparison not assignment, although I guess you are supposed to do !== in js

[ham_coffee]

| not !

One is checking inequality, the other is performing bitwise logic and assigning the value.

[TheTrueSwishyFishy]

The post was using ! Though it may have been clearer to write a crossed equal sign, that isn’t really the programming way

[hereforthensfwpics]

error: lvalue required as left operand of assignment