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My teacher is teaching us about sets, and he said that the '|', the ':' and the '\' symbols can be used to mean 'such that'. I'm certain of the first two, but I searched a little and couldn't find reference to the last. Does it exist for this purpose? If it's a special character, what Unicode code point does it have?

Thanks in advance.

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    I've never seen it used that way, and I've read a fair amount of obscure historical material about set theory that uses obsolete notation.2012-08-16
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    I've never seen something like '\' used for that purpose.2012-08-16
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    @HenningMakholm: I guess the OP meant “/”.2012-08-16
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    @PseudoNeo While writing by hand, sombody writes $/$ instead of $\mid$ to denote the vertical bar. Probably because it is easier to write :-)2012-08-16
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    @Siminore: Twas my point ;-) I also know of people who use “/” even when typesetting.2012-08-16
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    I have seen "/" used first time in my life very recently.2012-08-16
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    I first saw this use of ‘/’ here; I find it rather disconcerting.2012-08-16
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    @PseudoNeo: I actually meant '\', as in backslash.2012-08-16
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    Thanks for all of the answers, but the one that better reassured me was @Mark Dominus'. I'm terrified of teachers that present us with their own version of things and make it look like they're standard. This was not the case though. It was more like "this symbol is also used". Perhaps he meant a '|' that got inclined when written, instead of the '\' character. Which is contradictory, since things get inclined to the other side in handwriting. Go figure. Glad I got this one clear: either ':' or '|' are the most common.2012-08-17
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    I didn't want to post it as an answer because there's a lot of stuff I haven't seen that nevertheless exists.2012-08-17
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    I use a semicolon, like so: $\{x ∈ X;\; φ(x)\}$. A professor of mine did so and I adapted this as well because it looks good and the semicolon is almost never used in any other way (as opposed to “$|$” or “$:$”).2014-02-13

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