Where should AND and OR be placed in multi-line conditional statements? [closed]

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A simple coding standard question:

Where should AND and OR be placed in conditional statements?

Option 1:

if (x = 1 
    AND y = 2
    AND z = 3)

if (x = 1 
    &&a开发者_如何转开发mp; y = 2
    && z = 3)

if (x = 1 
    OR y = 2
    OR z = 3)

if (x = 1 
    || y = 2
    || z = 3)

Option 2:

if (x = 1 AND 
    y = 2 AND
    z = 3)

if (x = 1 &&
    y = 2 &&
    z = 3)

if (x = 1 OR
    y = 2 OR
    z = 3

if (x = 1 ||
    y = 2 ||
    z = 3)

I personally prefer option 1, since it allows you quickly comment out certain conditions - i.e. with "//" in most scripting languages, but I see option 2 more often, especially in code formatters.

Is there a standard?

What do you prefer?

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In "Code Complete," 2nd ed., pp 754-755, Steve McConnell lists the advantages of both patterns of line continuation.

The first identifies incomplete lines, but the operators are hidden in a ragged row.

The second highlights the operators. This can be important if the operators differ.

Compare:

  float total = ticketSalesBefore + 
                ticketSalesOnDayOfConcert + 
                tShirtSales -
                finesFromLocalPolice; 

to:

  float total = ticketSalesBefore
                + ticketSalesOnDayOfConcert
                + tShirtSales
                - finesFromLocalPolice; 

I personally prefer the second, and recommended including it during a review of McConnell's draft for that chapter.

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Option 1, absolutely, for the same reasons you mentioned. Easy to comment out, easy to duplicate, etc.

However, if they are small conditionals like you mentioned, I would put them all on one line.

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I prefer Option 1 because it highlights the tests. For Python coding I generally agree with PEP 8, but they go with Option 2 for this one.