WEBVTT

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Structures work exactly the same as any other data type when it comes to using them with functions.

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So here this example we have our book that we defined last time and we're passing a book type by value

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to this function func and doesn't do anything it's really just for illustration.

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But I would run this and show you the size of a book versus the size of an integer.

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So it's see this venture is four bytes.

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We saw this in the second section.

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And the size of the book type is 524 bytes OK.

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It's it's quite a bit bigger than just a simple integer now and doing copy's which is what we would

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do here we're passing a copy of a book to func and doing copies of bigger types that we make are usually

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a bad idea because it not only takes more space but but it's also slower because you're copying lots

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of data.

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And in fact in our case here this book type the copy wouldn't even work properly since there's now there's

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no there's no way you can copy an array without using something like Sturr copy.

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OK so we don't actually get a real proper copy for our book.

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OK.

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So instead of doing what I did here what I typically do is pass trucks by reference.

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OK so I'll do actually something more like this.

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OK.

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That way we're only passing the address of the struct which is much faster and smaller in terms of memory

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footprint because now an address is probably only about 8 bytes or 4 bytes it depends on your system.

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And if I don't want my functions to be able to change destructs I will pass them by constant reference

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to something like this.

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So that if I just want to look at the type K for I want to change a tire.

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I wouldn't use Konst.

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So with our Strax our own user defined types we will be passing them by reference or possibly by pointer

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depends on the situation.

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OK so that's the convention we'll be using when passing struts to functions and we'll look at structures

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with pointers in the next lecture.