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Deference between procedure and function?

11th Oct 2020, 5:59 AM
Muhammad
Muhammad - avatar
8 Réponses
+ 6
Self-contained blocks of your program, that usually have a name and can be invoked at will, are also called subroutines. A procedure is typically a block of instructions that just does things in sequence, but there is no result to return to the caller. A function does some calculations based on its parameters, and returns the result to the caller (where it might be assigned to a variable or printed). A method is a function declared inside a class in object oriented programming.
11th Oct 2020, 6:22 AM
Tibor Santa
Tibor Santa - avatar
+ 6
Lol Jan Markus It is correct to say that each programming language uses a bit different terminology... According to the "Zeitgeist", the ideas that were fashionable at the time of language design. So this can be confusing for learners. Even I got confused today, by the fact that Ruby functions are described as "method" throughout the course, although there are no objects involved, they are really just standalone functions. Python functions, even if we don't write a return statement, implicitly return None. So it is still correct to call them functions.
11th Oct 2020, 6:40 AM
Tibor Santa
Tibor Santa - avatar
+ 4
iirc, in PL/SQL, a function *must* return value. a procedure also *can* return value, but it's NOT compulsory to return it.
11th Oct 2020, 6:24 AM
🇮🇳Omkar🕉
🇮🇳Omkar🕉 - avatar
+ 4
Tibor Santa Regarding Ruby / Python - methods vs functions... it does appear that Ruby methods should be functions. But, in reality, what may appear to be global functions are in fact methods bound to the root Object instance. So, in Ruby, these are actually methods. https://stackoverflow.com/a/8393639/5087494 As far as Python returning None... that's actually an easier pill for me to swallow considering so many other language oddities I can't seem to get past my uvula due to an involuntary gag reflex. 🤣😂
11th Oct 2020, 8:05 AM
David Carroll
David Carroll - avatar
+ 3
FWIW... this thread on StackExchange covers the scenarios quite well in grasping the differences between procedures and functions across a variety of perspectives, vernaculars, and backgrounds. https://softwareengineering.stackexchange.com/questions/20909/method-vs-function-vs-procedure/20948#20948 I might add that in VB.NET and classic VB, the Sub and Function keywords are used to defined callable routines such that Sub (routines / procedures) do not return a value, while Functions do.
11th Oct 2020, 8:22 AM
David Carroll
David Carroll - avatar
+ 3
MZ Ahmadzai 🇦🇫 if you are specifically interested in PL/SQL then I recommend to read this, Oracle started republishing their introductory PL/SQL tutorial and it does mention also this topic: https://www.oracle.com/news/connect/plsql-101-part-1.html Quoted from the article: "PL/SQL supports the definition of named blocks of code, also known as subprograms. Subprograms can be procedures or functions. Generally, a procedure is used to perform an action and a function is used to calculate and return a value."
11th Oct 2020, 8:27 AM
Tibor Santa
Tibor Santa - avatar
+ 2
In C, a procedure can be 'modeled' by a function that returns void.
12th Oct 2020, 12:48 PM
Sonic
Sonic - avatar
+ 1
Tibor Santa , ok thanks , definitely I'll check for
12th Oct 2020, 6:05 AM
Muhammad
Muhammad - avatar