GameMaker ("+=" / "*=") operators limitations

[xDGameStudios]

I came across something I thought should be possible to do (at least it works with C++ and C# and JS.

if I try something like:

var m = 2

return ( ( m*= 2 ) * m + 3);

I get a syntax error, is it OK?
thank you for your time!

 

[NPT]

It doesn't make sense for the parenthesis to be on both sides of the *= as you have them.


return ( m*= 2 * m + 3);

Now, what value do you intend on returning?

 

[xDGameStudios]

It doesn't make sense for the parenthesis to be on both sides of the *= as you have them.


return ( m*= 2 * m + 3);

Now, what value do you intend on returning?

It doesn't make sense?! Why is that... I only wrote like that because of the multiplication order...

i didn't know if it would interfere... and BTW... you could have tried before coming here correcting people... the parentheses may be useless... but that's not the problem.. try it yourself and see!

 

[YellowAfterlife]

In a number of C-like languages,

return ( ( m*= 2 ) * m + 3);

would be interpreted as

m *= 2;
return m * m + 3;

However, the tendency with newer languages is to not allow such "inline assignments", as they are nothing other than asking for trouble (if compiler evaluation order is RTL, the expression will have an entirely different value - same as with function arguments), and are overwhelmingly used to cut some lines of code at price of making it harder to read.