Don't put a space between an em-dash and the adjacent words.
Alex in Florida asked, "Should there be a space before and after a dash?"
Every style guide I checked, except the AP Stylebook, stated there should be no spaces between an em-dash and the adjacent words. That means it is a style choice. If you're writing for a newspaper, magazine, or website that uses Associated Press style, put in the spaces. Otherwise, leave them out.
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