Good Examples of Hungarian Notation? [closed]

Question

This question is to seek out good examples of Hungarian Notation, so we can bring together a collection of these.

Edit: I agree that Hungarian for types isn't that necessary, I'm hoping for more specific examples where it increases readability and maintainability, like Joel gives in his article (as per my answer).

Answer 1

I find myself using 'w' meaning 'working', as a prefix instead of 'temp' or 'tmp', for local variables that are just there to jockey data around, like:

Public Function ArrayFromDJRange(rangename As Range, slots As Integer) As Variant

' this function copies a Disjoint Range of specified size into a Variant Array 7/8/09 ljr

Dim j As Integer
Dim wArray As Variant
Dim rCell As Range

wArray = rangename.Value ' to initialize the working Array
ReDim wArray(0, slots - 1) ' set to size of range
j = 0

For Each rCell In rangename
    wArray(0, j) = rCell.Value
    j = j + 1
Next rCell

ArrayFromDJRange = wArray

End Function

Answer 2

p

(for pointer). Its pretty much the only prefix I use. I think it adds a lot to a variable (eg that its a pointer) and so should be treated a little more respectfully.

Hungarian for datatypes is somewhat passe now IDEs can tell you what the type is (in only a few seconds hovering over the variable name), so its not so important. But treating a pointer as if its data is not good, so you want to make sure it's obvious to the user what it is even if he makes assumptions he shouldn't when coding.

Answer 3

The name of the variable should describe what it is. Good variable naming makes Hungarian notation useless.

However, sometimes you'd use Hungarian notation in addition to good variable naming. m_numObjects has two "prefixes:" m_ and num. m_ indicates the scope: it's a data member tied to this. num indicates what the value is.

I don't feel hindered at all when I read "good" code, even if it does contain some "Hungarian." Right: I read code, I don't click it. (In fact, I hardly use my mouse ever when coding, or any voodoo programming-specific lookup features.)

I am slowed when I read things like m_ubScale (yes, I'm looking at you, Liran!), as I have to look at its usage (no comments!) to find out what it scales (if at all?) and it's datatype (which happens to be a fixed-point char). A better name would be m_scaleFactor or m_zoomFactor, with a comment as a fixed-point number, or even a typedef. (In fact, a typedef would be useful, as there are several other members of several classes which use the same fixed-point format. However, some don't, but are still labeled m_ubWhatever! Confusing, to say the least.)

I think Hungarian was meant to be an additive to the variable name, not a replacement for information. Also, many times Hungarian notation adds nothing at all to the variable's readability, wasting bytes and read time.

Just my 2¢.

Answer 4

m

When using an ORM (such as hibernate) you tend to deal managed and unmanaged objects. Changing an managed object will be reflected in the database without calling an explicit save, while dealing with a managaged object requires an explicit save call. How you deal with the object will be different depending on which it is.