How to escape '|" character into an org-mode table - emacs

I am building some tables in org-mode and I need to enter "||" into the table (for the logical OR command) and nothing I try turns the two characters off as table constructors.
I've tried single quotes, double quotes, backticks and prefacing them with '\'. I've also tried every permutation of using ':=' to get a literal string and they don't work.
// Tony Williams

Depending on what you want to do with the output of the table, you could use alternative unicode characters that look like vertical pipes (or double vertical pipes). Examples:
This is the pipe character written twice (as for logical OR):
||
Those are similar (or not too different) looking unicode characters
‖ - ¦¦ - ❘❘
Of course, this won't work for you if you are not just interested in the looks (but escaping pipes would not work either).
See here more unicode characters you might like better than those 3 above

It turns out that you can use HTML entities in org-mode tables for output via pandoc.
\vert{} doesn't work but I went to the table pointed to by MrSpock and tried the HTML entity and the output when run through pandoc was perfect. || gives me '||'. I also tested a few other HTML entities and they also worked fine.

Well, if the goal is to export your notes, then
$\lvert\mathbb{N}\rvert$
would be an equivalent of
$|\mathbb{N}|$

Character is: \vert
Example: a \vert\ b -> a | b

Related

How to escape '|' in emacs's org-mode? [duplicate]

I've got a table in Emacs org-mode, and the contents are regular expressions. I can't seem to figure out how to escape a literal pipe-character (|) that's part of a regex though, so it's interpreted as a table-cell separator. Could someone point me to some help? Thanks.
Update: I'm also looking for escapes for a slash (/), so that it doesn't trigger the start of an italic/emphasis sequence. I experimented with \/ and \// - for example, suppose I want the literal text /foo/ in a table cell. Here are 3 ways of attempting it:
| /foo/ | \/foo/ | \//foo/ |
In LaTeX export, that becomes:
\emph{foo} & \/foo/ & \//foo/
So none of them is the plain /foo/ I'm hoping for.
\vert for the pipe.
Forward slashes seem to work fine for me unescaped when exporting both to HTML and PDF.
Use a broken-bar character, “¦”, Unicode 00A6 BROKEN BAR. This may or may not work for your specific needs, but it’s a good visual approximation.
You could also format the relevant text as verbatim or code:
Text in the code and verbatim string is not processed for Org mode
specific syntax; it is exported verbatim.
So you might try something like =foo | bar= (code) or foo ~|~ bar (verbatim). It does change the output format, though.

Replace characters with multi-character strings

I am trying to replace German and Dutch umlauts such as ä, ü, or ß. They should be written like ae instead of ä. So I can't simply translate one char with another.
Is there a more elegant way to do that? Actually it looks like that (not completed yet):
SELECT addr, REPLACE (REPLACE(addr, 'ü','ue'),'ß','ss') FROM search;
On my way trying different commands I got another problem:
When I searched for Ü I got this:
ERROR: invalid byte sequence for encoding "UTF8": 0xdc27
Tried it with U&'\0220', it didn't replace anything. Only by using ü (for lowercase ü) it was replaced correctly. Has to do something with unicode, but how to solve this issue?
Kind regards from Germany. :)
Your server encoding seems to be UTF8.
I suspect your client_encoding does not match, which might give you a wrong impression of what you are dealing with. Check with:
SHOW client_encoding; -- in your actual session
And read this related answers:
Can not insert German characters in Postgres
Replace unicode characters in PostgreSQL
The rest of the tool chain has to be in sync, too. When using puTTY, for instance, one has to make sure, the terminal agrees with the rest: Change settings... Window -> Translation -> Remote character set = UTF-8.
As for your first question, you already have the best solution. A couple of umlauts are best replaced with a string of replace() statements.
As you seem to know already as well, single character replacements are more efficient with (a single) translate() statement.
Related:
Replace unicode characters in PostgreSQL
Regex remove all occurrences of multiple characters in a string
Beside other reasons I decided to write the replacement in python. Like Erwin wrote before, it seems there is no better solution as combining replace- commands.
In general pretty simple, even no encoding had to benn used. My "final" solution now looks like this:
ger_UE="Ü"
ger_AE="Ä"
ger_OE="Ö"
ger_SS="ß"
dk_AA="Å"
dk_OE="Ø"
dk_AE="Æ"
cur.execute("""Select addr, REPLACE (REPLACE (REPLACE( REPLACE (REPLACE (REPLACE (REPLACE(addr, '%s','UE'),'%s','OE'),'%s','AE'),'%s','SS'),'%s','AA'),'%s','OE'),'%s','AE')
from search WHERE x = '1';"""%(ger_UE,ger_OE,ger_AE,ger_SS,dk_AA,dk_OE,dk_AE))
I am now looking forward to the speed when it hits the large table. If anyone would like to make some annotations, they are very welcome.

Escape pipe-character in org-mode

I've got a table in Emacs org-mode, and the contents are regular expressions. I can't seem to figure out how to escape a literal pipe-character (|) that's part of a regex though, so it's interpreted as a table-cell separator. Could someone point me to some help? Thanks.
Update: I'm also looking for escapes for a slash (/), so that it doesn't trigger the start of an italic/emphasis sequence. I experimented with \/ and \// - for example, suppose I want the literal text /foo/ in a table cell. Here are 3 ways of attempting it:
| /foo/ | \/foo/ | \//foo/ |
In LaTeX export, that becomes:
\emph{foo} & \/foo/ & \//foo/
So none of them is the plain /foo/ I'm hoping for.
\vert for the pipe.
Forward slashes seem to work fine for me unescaped when exporting both to HTML and PDF.
Use a broken-bar character, “¦”, Unicode 00A6 BROKEN BAR. This may or may not work for your specific needs, but it’s a good visual approximation.
You could also format the relevant text as verbatim or code:
Text in the code and verbatim string is not processed for Org mode
specific syntax; it is exported verbatim.
So you might try something like =foo | bar= (code) or foo ~|~ bar (verbatim). It does change the output format, though.

How to use '^#' in Vim scripts?

I'm trying to work around a problem with using ^# (i.e., <ctrl-#>) characters in Vim scripts. I can insert them into a script, but when the script runs it seems the line is truncated at the point where a ^# was located.
My kludgy solution so far is to have a ^# stored in a variable, then reference the variable in the script whenever I would have quoted a literal ^#. Can someone tell me what's going on here? Is there a better way around this problem?
That is one reason why I never use raw special character values in scripts. While ^# does not work, string <C-#> in mappings works as expected, so you may use one of
nnoremap <C-#> {rhs}
nnoremap <Nul> {rhs}
It is strange, but you cannot use <Char-0x0> here. Some notes about null byte in strings:
Inserting null byte into string truncates it: vim uses old C-style strigs that end with null byte, thus it cannot appear in strings. These strings are very inefficient, so if you want to generate a very large text, try accumulating it into a list of lines (using setline is very fast as buffer is represented as a list of lines).
Most functions that return list of strings (like readfile, getline(start, end)) or take list of strings (like writefile, setline, append) treat \n (NL) as Null. It is also the internal representation of buffer lines, see :h NL-used-for-Nul.
If you try to insert \n character into the command-line, you will get Null shown (but this is really a newline). If you want to edit a file that has \n in a filename (it is possible on *nix), you will need to prepend newline with backslash.
The byte ctrl-# is also known as '\0'. Many languages, programs, etc. use it as an "end of string" marker, so it's not surprising that vim gets confused there. If you must use this byte in the middle of a script string, it sounds like your workaround is a decent one.

What is '`' character called?

I feel silly for asking this but it isn't like I could google this.
What is the ` character called? In case it doesnt show up, it is the character used for inline code with markdown. Also, on most keyboards, it shares the key with ~.
I like all three answers so I made this a CW instead of accepting
All sorts of things, but in programming mostly the back-quote or backtick,
Grave (pronounced Grahv, not like the synonym for tomb) or Grave accent.
From the Jargon file, the prime nerd reference which really should be an ISO standard :-)
Common: backquote; left quote; left single quote; open quote; ; grave.
Rare: backprime; backspark; unapostrophe; birk; blugle; back tick; back glitch; push; opening single quotation mark; quasiquote.
You can use Unicode table to find name of the symbol. There are utilities which let you search it, like gucharmap. It gives U+0060 GRAVE ACCENT for this symbol.
This answer or this answer provides a good definition.
In laymen's terms "no-shift-tilde" is also useful in PHP for keeping mySQL statements from crashing on single quotes on the table name.
SELECT * from `the_table_name` WHERE id=1 // best practice
For some reason certain PHP servers will choke on this:
SELECT * from 'the_table_name' WHERE id=1 // not preferred method
This normally works, but doesn't pass nice in strings:
SELECT * from "the_table_name" WHERE id=1 // how to escape this string?
Other than that, I don't use it much.