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General Discussion

Posted by kingedwards
kingedwards
5,977 Points

Is there a reason to use i+= 1 and not I++?

.

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Edwards,

What lesson is this for?

Or at least what language is this for and I can change the category from "general discussion" to something more relevant.

1 Answer

Steven Parker
Steven Parker
231,126 Points
Steven Parker
Steven Parker
231,126 Points

Assuming your language supports both operations, one reason the first one might be preferred is simply for readability, since the increment amount is part of the expression. Another reason might be flexibility, as you can change the increment amount simply by changing the digit.

But a potentially more important reason for the choice would be if these expressions are used as part of larger expressions or statements, they have different values. The addition assignment operation ("i+=1") has the value of the final assignment, but the post-increment operation ("i++") has the value of the variable before the increment is performed. For example:

a = b = 6;       // start with a and b both 6
x = (a += 1);
y = b++;
// at this point, a and b are both 7, and x is also 7 but y is 6