Hard code or portable code

[hershrev]

Very good explanation .
Thanks , hershrev
On Thursday, March 11, 2004, at 01:31 AM, J. Landman Gay wrote:

> On Wednesday, March 10, 2004, at 04:09 PM, hershrev wrote:
>>
>> Can I please have a little understanding on the parameter part of 
>> functions what does it do or add?
>
> The following is kind of long, so apologies in advance. I wrote it for 
> someone else a long time ago. The person I was writing to said he 
> never used custom functions because he didn't know what they were. He 
> asked me to explain.
>
> ***
>
> If Revolution does not have a built-in function to do something you 
> want, you can write your own function to do it instead. Suppose we 
> want to add two numbers together and get a total. (This is a very 
> simple example, and really you would not need to do this because MC 
> can add two numbers easily inside a script. But it makes a good 
> example.) So we can write a function called "addNumbers" like this:
>
> function addNumbers num1,num2
>   put num1 + num2 into theTotal
>   return theTotal
> end addNumbers
>
> The parameters "num1" and "num2" are like baskets that hold whatever 
> values the original handler sends to the function. In this case, they 
> each will contain a number. The special word "return" tells Revolution 
> to send the variable "theTotal" back to the handler that asked for the 
> information. So, this function takes two numbers that are passed to it 
> in the parameters, adds them together, and sends back a total. Now we 
> can write a handler that uses this function this way:
>
> on myHandler
>  put 16 into theFirstNumber
>  put 4 into theSecondNumber
>  put addNumbers(theFirstNumber,theSecondNumber) into myTotal
> end myHandler
>
> This handler will send "16" and "4" to our custom function 
> "addNumbers". The addNumbers function will catch these two numbers in 
> its parameters "num1" and "num2", then add them together, and send 
> back "20". The script "myHandler" will receive that 20 and put it into 
> the variable "myTotal". So myTotal now equals 20.
>
> When you use a function in a handler, you must provide a place for its 
> results to go -- a variable usually, or sometimes a field. For 
> example, this will not work:
>
>   addNumbers(theFirstNumber,theSecondNumber)
>
> because there is no place for the returned information to go. A 
> handler that uses a function must provide a place to store the 
> information that the function sends back. This is true of built-in Rev 
> functions too. For example, this will not work:
>
>   the date
>
> because there is no place for the date to be stored. You must provide 
> a place:
>
>   put the date into myDate
>
> A handler that uses a custom function must follow the same rule. It 
> must provide a place for the returned information to be stored:
>
>   put addNumbers(theFirstNumber,theSecondNumber) into myTotal
>
> Functions can be as short or as long as you want, and sometimes can be 
> very complicated. But the basics are always the same: a handler asks a 
> function to do some work and often sends some parameters to the 
> function to tell it what to use for that work. The function does the 
> work and returns the finished calculation to the original handler. The 
> handler can use the finished calculation any way it wants, just as if 
> it were any other variable.
>
> -- 
> Jacqueline Landman Gay         |     jacque at hyperactivesw.com
> HyperActive Software           |     http://www.hyperactivesw.com
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