Problems Error Trapping Integers

[olafsonemily]

Hello! I have a grade 9 Turing exam approaching, and I noticed a problem that would pop up occasionally when I was error trapping integers. If anyone can tell me how to error trap for integers using either strint or strintok without making my locx variable a string, it would be much appreciated. Thanks in advance!



I've tried using strint and strintok, but it seems that the only way I can error trap for integers is by turning it into a string like so:

Turing:

var locx : string get locx if strintok (locx) then else     put "Sorry, please enter an integer." end if

And if I do that, I cannot error trap for if the integer that was input is outside a certain range, as it must be an integer, not a string. Anything helps, my exam is on the 20th.

Here's my code so far, you'll notice an error with "intstr".

Turing:

var locx : int proc userInput     var key : string (1)     locate (5, 1)     put "Please enter the location of the star on the x-axis: " ..     get locx     if locx > 640 or locx < 0 then         put "sorry, that is not within the limit of the screen. Please enter a number between 0 and 640."         put "Press any key to try again " ..         getch (key)         userInput     end if     if intstr (locx) then         put "Sorry, please enter an integer."     else     end if end userInput userInput

Using Turing 4.1

[Raknarg]

intstr does not result a boolean, it results a string from an integer. That's what strintok is for. If strintok (input) results a false, then it means you cant convert the string to an integer. If it's true, then you can. Use that knowledge for errorchecking.

[Dreadnought]

You can check if the string can be converted to an integer. Then convert it and check if its within the bounds (if it can be converted).

You'll need to use a nested if statement, but it shouldn't be too tough.