Marking plural of code words

In my blog (which is about programming) I often use reserved words from different programming languages.

Like this:

When column is nullable in both tables, this query won't return a match of two NULLs for the reasons described above: no NULLs are equal.

Here, NULL is a programming language keyword.

For numerous reasons, I mark them with <code> tag so they are rendered with a fixed width font, not translated into the foreign languages by Google Translate, can easily be seen on the page etc.

In the example above, which would be the best way to mark the plural?

1. NULLs
2. NULL s
3. NULL's
4. NULLs
5. NULLS

Option 1 looks ugly on the page (the word and the plural marker are rendered in different colors and fonts)

Option 2 adds a space between the word and the plural marker

Option 3 looks nicest but is not correct

Options 4 and 5 may leave the reader under impression that NULLS is a reserved word (which is not true) and this may be confusing. Also, Google Translate would leave the word as is which would be definitely wrong in other languages.

What would be the least of 5 evils?

Solution 1:

Definitely don't use an apostrophe or a capital S to pluralize NULL.

As a programmer, I'd suggest formatting it as NULLs. I think your readers will understand that.

I'd also recommend considering rewriting sentences like that to obviate the need to pluralize NULL. For example:

When column is nullable in both tables, this query won't return a match of two NULL values for the reasons described above: no NULL values are equal.

Solution 2:

You don't have to pluralize these code words, because you can always write them as adjectives. For example:

• How to compare NULL values

• Do not write too many nested while blocks.

• Make sure that you map the getDatabasePrimaryKey() methods.