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PHP

Posted by Philip Harper
Philip Harper
10,033 Points

What is an "Argument"?

Ok, please don't laugh.

I've been learning to tinker with PHP and this word "Argument" keeps coming up and again in the tutorials.

In programming, what does this mean? Seriously, I don't know. I'm ashamed and embarrassed and ashamed, I don't know.

I asked on Stackoverflow but got laughed off stage. It seems it's almost TOO basic, that EVERYONE should know this computer based concept. Even those that don't programme.

Thanks, everyone.

I feel better now I've asked.

2 Answers

Ryan Duchene
Ryan Duchene
Courses Plus Student 46,022 Points

No problem, man. Everyone has to start somewhere. :)

An argument is a piece of information that you give to a function. A function is an action; it goes and does something. An argument is an object that the function works with to accomplish something.

You can think of an argument as a secretary. You hand a letter to a secretary and say "Mail this."

<?php

function mail($letter)
{
  // mails the $letter
}

You can make a function can take more than one arguments. You hand a letter and a stamp to the secretary and say "Put the stamp on the letter and mail it."

<?php

function mail($letter, $stamp)
{
  // puts the $stamp on the $letter
  // mails the $letter
}

The analogy isn't perfect, but it's the best I could come up with. So now, to actually stamp and mail your letter, you need to actually call the function.

<?php

mail($my_letter, $my_stamp);

Does that help you at all? I can try to simplify it if you want, or find a better analogy. It just takes time and practice to get used to these things, that's all. Treehouse is great with both. :)

Christian Andersson
Christian Andersson
8,712 Points

Good answer and example.

I'd like to think of a function as a piece of code that is "cocooned" from any code that's outside of it. So if information from the main program needs to be given to this isolated piece of code it needs to be passed in the argument.

EDIT: Oh, and the people over at StackOverflow are usually #&!%

jne
jne
12,613 Points
jne
jne
12,613 Points

At php.net they have a manual to cover all you need to know about php. Here's a link about arguments http://php.net/manual/en/functions.arguments.php