Grammatically Correct: The writer's essential guide to punctuation ...

PUNCTUATION
the discussions of the hyphen as a component of spelling on page
23, and as a punctuation mark on page 125.)
A tricky situation can arise when two of these situations combine:
that is, if you need to link two entities that themselves contain
hyphens. For example:
The anti-conscription-pro-conscription debate was turning into a
shouting match.
In situations such as this, use the longer en dash to link the
compounds.
The anti-conscription-pro-conscription debate was turning into a
shouting match.
You face a similar problem with an open compound (a compound
where each word stands alone) because it may look like only the
word closest to the hyphen is linked to what precedes or follows.
For example, writing the ex-prime minister looks-just a littlelike
a reference to a minister who is no longer in his prime! Again,
the solution is to use an en dash in place of the hyphen.
the ex-prime minister
a non-computer expert
a credit card-sized calculator
the Quebec City-Montreal flight
STYLE CONVENTIONS
• If you can't create an en dash, use a hyphen or an em dash.
If your text is going to be properly typeset, the mark will be changed
before publication.
• Do not leave spaces around an en dash: Always have it lie
directly against the adjoining text on both sides.
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