In the Pascal programming language you have Procedures and Functions. Procedures are used when you want to modify multiple variables within a sub-program. A function is a sub-program that returns a single value after it has been modified by say a formula. EasyLanguage combines procedures and functions into one sub-program called a function. Functions and procedures both have a formal parameter definition – a list that describes the type of parameters that are being received by the calling program. In Pascal procedures, you pass the address of the value that you want changed. By modifying the contents of the address you can pass the value back and forth or in and out of the procedure. In functions you pass by value. Remember the parameter in a normal function call is used to instruct something within the body of the function and is not altered (e.g. the number 19 in value1 = average(c,19)). This value doesn’t need to be modified it’s just used. Look at the following code:
Here I am modifying mav1, mav2 and mav3 within the function and then passing the values back to the calling strategy/indicator/paintbar. All functions must return a value so I simply assign the value 1 to the function name. The key here is the keyword numericRef, once I change the values located in the addresses of mav1, mav2 and mav3 (address are provided by the keyword numericRef), they will be made available to the calling program. This code allows the function to return more than just one value.
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