BRIEF: can the characters permitted in org-mode tags be extenced in any way?
E.g. to include -, dashes?
DETAIL:
I see
http://orgmode.org/org.html#Tags
Tags are normal words containing letters, numbers, ‘_’, and ‘#’. Tags
must be preceded and followed by a single colon, e.g., ‘:work:’.
I am somewhat surprised that this is not extensible. Is it, and I have missed it?
TODO keywords can include dashes. Occasionally I would like to treat TODOs as intermiscible wth tags - e.g. move a TODO to a tag, and vice versa - but this syntax difference gets in the way.
Before I start coding, does anyone know why dashes are not allowed? I conjecture confusion with timestamps.
Not certain, but it is likely because certain agenda search strings use "-" as an operator, and there is not yet a way to escape those using "-".
I have used hyphens for properties and spaces for todo kw with no problems for my purposes, but I have not tried them in searches.
The new exporter will be included in 8.0 and with it a detailed description of syntax. If you want to file a feature request to allow hyphens, perhaps by allowing escaping in search strings, now is the time to do it.
Related
Disclaimer: I have no engineering background whatsoever - please don't hold it against me ;)
What I'm trying to do:
Scan a bunch of text strings and find the ones that
are more than one word
contain title case (at least one capitalized word after the first one)
but exclude specific proper nouns that don't get checked for title case
and disregard any parameters in curly brackets
Example: Today, a Man walked his dogs named {FIDO} and {Fifi} down the Street.
Expectation: Flag the string for title capitalization because of Man and Street, not because of Today, {FIDO} or {Fifi}
Example: Don't post that video on TikTok.
Expectation: No flag because TikTok is a proper noun
I have bits and pieces, none of them error-free from what https://www.regextester.com/ keeps telling me so I'm really hoping for help from this community.
What I've tried (in piece meal but not all together):
(?=([A-Z][a-z]+\s+[A-Z][a-z]+))
^(?!(WordA|WordB)$)
^((?!{*}))
I think your problem is not really solvable solely with regex...
My recommendation would be splitting the input via [\s\W]+ (e.g. with python's re.split, if you really need strings with more than one word, you can check the length of the result), filtering each resulting word if the first character is uppercase (e.g with python's string.isupper) and finally filtering against a dictionary.
[\s\W]+ matches all whitespace and non-word characters, yielding words...
The reasoning behind this different approach: compiling all "proper nouns" in a regex is kinda impossible, using "isupper" also works with non-latin letters (e.g. when your strings are unicode, [A-Z] won't be sufficient to detect uppercase). Filtering utilizing a dictionary is a way more forward approach and much easier to maintain (I would recommend using set or other data type suited for fast lookups.
Maybe if you can define your use case more clearer we can work out a pure regex solution...
I haven't been able to find in Drools documentation, which characters (beyond alphabet letters) are allowed/disallowed in a rule name in Drools - does anyone know or have a reference?
The only relevant section of Drools doc I've found so far does not specify:
Each rule must have a unique name within the rule package. If you use the same rule name more than once in any DRL file in the package, the rules fail to compile. Always enclose rule names with double quotation marks (rule "rule name") to prevent possible compilation errors, especially if you use spaces in rule names.
I think I have discovered, anecdotally, that some "grouping" characters do not work in rule names (seems rules named with can't be found or aren't included) - or at least, in extension rules (the extended rule seems to work with grouping chars, but not its extension; example below): The grouping chars include parentheses "()", square brackets "[]", and "curly braces" "{}". Although less than & greater than "<>" work, so I'm so far replacing the former with the latter.
Or are there escape chars for the problematic grouping chars?
Example:
rule "(grouping chars, and commas, work here)"
when
// conditions LHS
then
end
// removing parentheses, or replacing with < >,
// from below line works
rule "(grouping chars DON'T work here)"
extends "(grouping chars, and commas, work here)"
when
then
// consequences RHS
I haven't discovered either way yet with all other characters (for example, other punctuation; except I have discovered commas "," work). But it would be nice to know ahead of time what characters are allowed.
Theoretically every identifier inside a string should work, but you might have empirically found some combination that is breaking the grammar somehow.
Thanks for the investigation, I've filled a Jira, please take a look at it
I'm coming across a strange situation where I cannot search on string tags that end with a special character. So far I've tried ) and ].
For example, given a Fruit index with a record with a tag apple (red), if you query (using the JS library) with tagFilters: "apple (red)", no results will be returned even if there are records with this tag.
However, if you change the tag to apple (red (not ending with a special character), results will be returned.
Is this a known issue? Is there a way to get around this?
EDIT
I saw this FAQ on special characters. However, it seems as though even if I set () as separator characters to index that only effects the direct attriubtes that are searchable, not the tag. is this correct? can I change the separator characters to index on tags?
You should try using the array syntax for your tags:
tagFilters: ["apple (red)"]
The reason it is currently failing is because of the syntax of tagFilters. When you pass a string, it tries to parse it using a special syntax, documented here, where commas mean "AND" and parentheses delimit an "OR" group.
By the way, tagFilters is now deprecated for a much clearer syntax available with the filters parameter. For your specific example, you'd use it this way:
filters: '_tags:"apple (red)"'
I'm trying to gather a Unicode list of all the 'o' like shapes in the Hindi character-set. In fact, a list of any characters (in any language) that makes uses of separate characters to indicate an accent would be better.
I intend to use this unicode-list in a RegExp.
I been trying to edit a list of character-ranges by outputting them in an Input TextField, but editing this text causes weird issues (the keyboard-cursor isn't place on the correct character, selections suddenly dissappear / incorrectly warps... in other words... HINDI HELL!)
I've tried this with Notepad++ too, but although it was more responsive, it eventually crapped out on me like it did in the Flash Player textfield. This seems to occur especially while removing the [] block (nulls?) characters. Some of them trigger odd behaviors.
Anyways, all I want is a list of the accents.
An example of a few are in the image below (but I would need ALL accents):
Thanks!
You can find pdf's containing lists of unicode ranges, grouped by language, here: http://unicode.org/charts/
For Hindi, you probably want Devanagari or Devanagari Extended.
Here is the character class for Devanagari combining marks:
[\u901\u902\u903\u93c\u93e\u93f\u940\u941\u942\u943
\u944\u945\u946\u947\u948\u949\u94a\u94b\u94c\u94d
\u951\u952\u953\u954\u962\u963]
This is only the basic Devanagari block (not Devanagari Extended).
If you want the complete set (for all languages), you can do it problematically.
You start from the Unicode date file at ftp://ftp.unicode.org/Public/6.1.0/ucd/UnicodeData.txt, described by TR-44 (http://unicode.org/reports/tr44/#Property_Definitions)
You can use the Canonical_Combining_Class field (see at http://unicode.org/reports/tr44/#Canonical_Combining_Class_Values) to filter the exact characters you want.
Can't be more precise, because "accent" a bit vague :-)
You might even have to also look at General_Category to get the filter right (and exclude certain marks, or symbols, or punctuation).
And a script doing this would definitely be better than trying to mess with text editors.
One of the characteristics of combining characters is that they combine :-)
So you might get all kind of puzzling results (like this: http://www.siao2.com/2006/02/17/533929.aspx :-)
What Unicode characters (more precisely codepoints) are dangerous and should be blacklisted and prohibited for the users to use?
I know that BIDI override characters and the "zero width space" are very prone to make problems, but what others are there?
Thanks
Characters aren’t dangerous: only inappropriate uses of them are.
You might consider reading things like:
Unicode Standard Annex #31: Unicode Identifier and Pattern Syntax
RFC 3454: Preparation of Internationalized Strings (“stringprep”)
It is impossible to guess what you mean by dangerous.
A Golden Rule in security is to whitelist instead of blacklist, instead of trying to cover all bad characters, it is a much better idea to validate based on ensuring the user only use known good characters.
There are solutions that help you build the large whitelist that is required for international whitelisting. For example, in .NET there is UnicodeCategory.
The idea is that instead of whitelisting thousands of individual characters, the library assigns them into categories like alphanumeric characters, punctuations, control characters, and such.
Tutorial on whitelisting international characters in .NET
Unicode Regex: Categories
'HANGUL FILLER' (U+3164)
Since Unicode 1.1 in 1993, there is an empty wide, zero space character.
We can't see it, neither copy/paste it alone because we can't select it!
It need to be generated, by the unix keyboard shortcut: CTRL + SHIFT + u + 3164
It can pretty much 💩 up anything: variables, function name, url, file names, mimic DNS, invalidate hash strings, database entries, blog posts, logins, allow to fake identical accounts, etc.
DEMO 1: Altering variables
The variable hijacked contains a Hangul Filler char, the console log call the variable without the char:
const normal = "Hello w488ld"
const hijaㅤcked = "Hello w488ld"
console.log(normal)
console.log(hijacked)
DEMO 2: Hijack URL's
Those 3 url will lead to xn--stackoverflow-fr16ea.com:
https://stackㅤㅤoverflow.com
https://stackㅤㅤoverflow.com
https://stackㅤㅤoverflow.com
See Unicode Security Considerations Report.
It covers various aspects, from spoofing of rendered strings to dangers of processing UTF encodings in unsafe languages.
U+2800 BRAILLE PATTERN BLANK - a Braille character without any "dots". It looks like a regular "space" but is not classified as one.