American standard style for (3) seems to be to use an em-dash and no spaces: I was—as you may know—pedantic. British style is to use an en-dash and spaces: I was – as you may know – pedantic. A minus sign is not a dash; it's its own symbol which I think is about as wide as an en-dash in most typefaces. Joining things which already have hyphens is just a losing proposition.
An em is a useful unit of length: it's the point size of the current typeface. In most typefaces not designed by monkeys, this is about the width of the character M. An em-dash is one em long. An en-dash is half as long as an em-dash, which, subject to earlier simian considerations, is about the width of an N.
All of this has no more authority than my own observation and some of the LaTeX documentation.
no subject
Date: 2007-03-16 11:50 pm (UTC)An em is a useful unit of length: it's the point size of the current typeface. In most typefaces not designed by monkeys, this is about the width of the character M. An em-dash is one em long. An en-dash is half as long as an em-dash, which, subject to earlier simian considerations, is about the width of an N.
All of this has no more authority than my own observation and some of the LaTeX documentation.