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Welcome back for a little way of

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the programmer advice on naming the variables in your for-loops.

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So, suppose that x was a variable whose bound to a list somewhere,

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you might be tempted to write for y and x print(y).

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The problem is, if you haven't looked at this code in awhile,

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and x was defined somewhere above this code, what is x?

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You haven't given it a name that gives any suggestion

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that it's even a list much less what it's a list have.

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I have for y and x also I'm not,

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with my code here I'm not giving any hint

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as to what kinds of items are supposed to be in x.

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So, this is a very simple for-loop,

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you might be able to get away with this and still be able to understand what's going on,

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but it's really going to be helpful if you give more meaningful names.

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One bit of advice I have is to,

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whenever you're having a variable name that's going to refer to a list,

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give it a plural noun as its name,

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and whenever you're going to have an iterator variable, give it a singular noun.

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So, here's an example in my next code window.

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I have a variable called genres.

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Because it has a plural name with an S on the end,

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I expect it to be probably a sequence.

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Then I took my iterator variable and I chose to make it be a singular noun.

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Moreover, it is a singular noun that goes with the plural noun So,

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each item in a list called genres is going to be one genre.

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And so, then in my code inside the for-loop,

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I'm going to refer to this singular variables genre

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and it's going to remind me that it's one item from the genres list.

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This is a lot better than doing things like,

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and I sometimes do see students confuse themselves.

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They'll say, "for apples in fruit", and fruit actually,

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you look at their code and it's a list of the names of fruits and

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apples is the first string that's in that list,

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and so somehow they decided that they would name the variable name apples,

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but this'll be very confusing to read because you get four lines into

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the code and you see apples somewhere, and you think, "Oh.

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Apples must be a list of different kinds of apples or something like that. "

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So, don't do this.

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For fruit in fruits, that's fine.

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So, for your sequence,

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do a plural noun.

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For your iterator variable,

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do a singular noun.

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Follow that little convention and you'll save yourself a lot of

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confusions as you're coding. See you next time.