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Hi,
So even though this question doesn't pertain to Acrobat I'm asking it here because it's a javaScript question.
I have a little scripting experience but I'm brand new to JavaScript.
Can someone please explain the example of the ++ operator found on this page?
The example is below so you don't actually need to follow the link.
Arithmetic operators - JavaScript | MDN​
// Postfix
var x = 3;
y = x++; // y = 3, x = 4
// Prefix
var a = 2;
b = ++a; // a = 3, b = 3
A little history...
I was trying to increment a variable by one through each iteration of a conditional statement.
I was trying to duplicate an item "x" number of times until "x" equaled 10.
I basically wrote the offending line of code as x = x++;
That statement sent the script into an infinite loop.
I did this based on my experience with MEL for Maya.
So from what I read & what was explained to me about JavaScript
I learned that unlike the other language I know
a postfix ++ operator would keep the variable the same &
a prefix ++ operator would increment it by one.
However in the above example I am confused by two things:
first: the inclusion of the second variable "b"
second: In both the postfix & prefix examples "x" gets incremented by one
If postfix is supposed keep the value the same & prefix is supposed to add 1, then why do both examples add 1?
For bonus points & if it's not too much trouble....
Pertaining the postfix operator keeping the same value....
Why might I want to add an operator to a variable that does nothing? (keeps it the same)
Thanks for taking the time to read this & I appreciate any help.
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The prefix-version executes before the rest of the code in that line. The
postfix-version executes after it.