Layout Control Characters

A note by David Gibson

You will already be familiar with some of Word's layout control characters, such as using shift-return to force a new line (or, if you are in find-and-replace, caret-lowercase-L. To further examples are ctrl-hyphen to insert an optional hyphen, and ctrl-shift-hyphen to insert a non-breaking hyphen. Two that you might not be familar with are the no-width optional break and no-width non-break. There is a particular use for no-width optional break when quoting URLs in Word documents.

There is a difficulty in quoting long URLs that cover multiple lines, because Word needs to be told where to break the URL to fit the line. If you put in manual line breaks and you later re-write the paragraph, you can end up with line breaks in the wrong places – and not notice till its too late. For this reason, I sometimes separate parts of a URL with a space. That is less prone to causing layout errors but it is still not ideal. Using Word's no-width optional break you can indicate where you would like Word to consider adding a line break – it is abit like using an optional hyphen except that it does not render as a visible hyphen. You could, for example, follow each occurance of slash with no-width optional break.

Word also provides no-width non-break, which is useful when you need to control Word's default behaviour regarding en-dashes and other variations on the hyphen; and when you are writing equations that Word insists on breaking in the wrong place

Word's no-width optional break is listed at the bottom of the Special Characters menu. It does not have a default shortcut key, but you can add one from the Special Characters dialogue. I have set ctrl-alt-space to mean no-width optional break on my system. That is similar to the built-in ctrl-shift-space for non-breaking space. The Special Characters menu can be displayed viaalt-I S alt-P or, at least, that's in my ancient version of Word. I think the keyboard shortcuts are the same in Office 365, although the pull-down menus are very different.

The two characters no-width optional break and no-width non-break are the Unicode characters zero width non-joiner (ZWNJ)and zero-width joiner (ZWJ). As HTML entities that is ‌ and ‍ or in Unicode U+200C andU+200D. To enter them on your numeric keypad, in Word – which is the way I find most convenient to insert en-dashes and other non-keyboard characters – it isalt-8204 and alt-8205.

When Word displays a document on screen it represents a layout control character by its particular special icon. But when it renders a document for printing, it replaces a layout control character by a printable character. So, for example, an optional hyphen would be rendered either as nothing, if it was not required, or as hyphen-newline. Thus, another advantage of using these characters is that it allows people to paste a URL from a PDF without collecting extraneous spaces or line breaks. FIXME CHECK THIS

In summary...

• The zero-width-non-joiner, which Word calls no-width optional break can be used to allow Word to break a long string at a controlled position. You can enter it from the numeric keypad as alt-8204 or from the Special Characters dialogue box
• The zero-width-joiner, which Word calls no-width non break is used to force Word to concatenate strings where it would normally insert a line break. You can enter it from the numeric keypad as alt-8205 or from the Special Characters dialogue box.