Take a look at Behaviour of increment and decrement operators in Python for an explanation of why this doesn't work. Python doesn't really have ++ and --, and I personally never felt it was such a loss. I prefer functions with clear names to operators with non-always clear semantics (hence the classic interview question about ++x vs. x++ and the difficulties of overloading it). I've also never ...
I have a formula in Excel that needs to be run on several rows of a column based on the numbers in that row divided by one constant. When I copy that formula and apply it to every cell in the range...
3 Pre-increment means that the variable is incremented BEFORE it's evaluated in the expression. Post-increment means that the variable is incremented AFTER it has been evaluated for use in the expression. Therefore, look carefully and you'll see that all three assignments are arithmetically equivalent.
First, the ++ operator takes precedence over the * operator, and the () operators take precedence over everything else. Second, the ++number operator is the same as the number++ operator if you're not assigning them to anything. The difference is number++ returns number and then increments number, and ++number increments first and then returns it. Third, by increasing the value of a pointer ...
This may seem like pedantry (mainly because it is :) ) but in C++, x++ is a rvalue with the value of x before increment, x++ is an lvalue with the value of x after an increment. Neither expression guarantees when the actual incremented value is stored back to x, it is only guaranteed that it happens before the next sequence point. 'after processing the current statement' is not strictly ...
My opinion is that a better response to the relation between 'if' statement and the post increment operator '++' requires the expansion of your C-code into Assembly.
7 This answer is a small addition to the highest voted answer and works for SQL Server. The question requested an auto increment primary key, the current answer does add the primary key, but it is not flagged as auto-increment. The script below checks for the columns, existence, and adds it with the autoincrement flag enabled.
In the declaration of the procedure "Increment", the parameters are enclosed by parentheses. When I type "Increment" to call the procedure, the little yellow help text box showing the expected syntax also has the parameters inside parentheses. But if I do write the parameters that way, the operation is not carried out.
