Comment by jader201 2 days ago
Anytime I do this — and I did it long before AI did — they are always em dashes, because iOS/macOS translates double dashes to em dashes.
I think there may be a way to disable this, but I don’t care enough to bother.
If people want to think my posts are AI generated, oh well.
I once spent a day debugging some data that came from an English doc written by someone in Japan that had been pasted into a system and caused problems. Turned out to be an en-dash issue that was basically invisible to the eye. No love for en-dash!
Similar.
Compiler error while working on some ObjC. Nothing obviously wrong. Copy-pasted the line, same thing on the copy. Typed it out again, no issue with the re-typed version. Put the error version and the ok version next to each other, apparently identical.
I ended up discovering I'd accidentally lent on the option key while pressing the "-"; Monospace font, Xcode, m-dash and minus looked identical.
This issue also exists with (so called) "smart" quotes.
Em dashes used as parenthetical dividers, and en dashes when used as word joiners, are usually set continuous with the text. However, such a dash can optionally be surrounded with a hair space, U+200A, or thin space, U+2009 or HTML named entities   and   These spaces are much thinner than a normal space (except in a monospaced (non-proportional) font), with the hair space in particular being the thinnest of horizontal whitespace characters.
https://en.wikipedia.org/wiki/Whitespace_character#Hair_spac...
Typographers usually add space to the left side of the following marks:
: ; ” ’ ! ? / ) ] } * ¿ › » @ ® ™ ℓ ° ¡ ' " † + = ÷ - – —
“ ‘ / ( [ { > ≥ < ≤ £ $ ¢ € ‹ « √ μ # @ + = ÷ - – —
1. (letterpress typography) A piece of metal type used to create the narrowest space. 2. (typography, US) The narrowest space appearing between letters and punctuation.
https://en.wiktionary.org/wiki/hair_space
Now I'd like to see how the metal type looks like, but ehm... it's difficult googling it. Also a whole collection of space types and what they're called in other languages.
That depends on the language — whereas German puts spaces around —, English afaik usually doesn’t.
Similarly, French puts spaces before and after ? ! while English and German only put spaces afterwards.
[EDIT: I originally wrote that French treats . , ! ? specially. In reality, french only treats ? and ! specially.]
french does "," and "." like the british and germans the rest is space befor space after
> Anytime I do this — and I did it long before AI did — they are always em dashes
It depends if you put the space before and after the dashes--that, to be clear, are meant to be there--or if you don't.