Using TeXShop to typeset LaTeX, I often come across the error Package inputenc error: Character \u8 not set up for use with LaTeX. That, I have learnt, is due to the fact that, for some reason, some spaces become "no-break space"s (U+00A0), which apparently inputenc doesn't like. So this is NOT a LaTeX question, but just one that was brought up by LaTeX. It might be about TeXShop or about I don't know what, but the LaTeX part is definitely solved. So the question is: why does it turn up? Is it a shortcut I am unaware of (I'm om Mac OS X 10.7.5), a TeXShop specific thing, or something else?
PS I'm not sure if the tag is appropriate. Were I not forced to give at least one, I probably would have given none. LaTeX, as stated above, is definitely NOT an appropriate tag for this question. The one I had put was probably more appropriate. Anyway I'll have a look at the list of popular tags (if I find one) and change the tag to the one that seems most appropriate to me.
As Wikipedia states on this page, Alt+Space on Mac inputs the No-Break Space. In speedy typing, I probably inadvertently press Alt while typing the space, resulting in this problem.
I want Sublime to treat my text files like they are source code files and show whitespace at the left of wrapped lines, like so:
beginning of long line blah blah blah, now it wraps
and it keeps going after an automatic indent
I tried opening the console and setting the option manually:
view.settings().set('indent_subsequent_lines', True)
but nothing changes, any ideas?
Well, that was fun. There's no easily accessible setting for this. But as you indicate, ST decides whether to add an extra indent when soft wrapping, from whether the syntax is considered code-like or plain text-like.
Being one or the other is up to the package defining the syntax to specify. So lacking a global setting from ST, you need to change your text packages. As an example, let's take Text. That contains Plain text.tmLanguage. In that you change
<key>scopeName</key>
<string>text.plain</string>
to
<key>scopeName</key>
<string>source.plain</string>
I'm unsure of whether there'll be ill effects from not keeping .plain.
One easy way to do this is to get the PackageResourceViewerpackage.
After install, do:
cmdshiftp
Type: Open Resource
return
Type: Text
return
Type: Plain text.tmLanguage
Make your edit and save.
PackageResourceViewer will save the modified Text package to your Packages directory. And sublime will display files considered to have Plain text-syntax, like they are code.
The caveat is that you need to do this for every text-syntax you want to be considered code.
As #AdamAL said, it's dependent on both the 'indent_subsequent_lines' setting as well as whether it's considered a "source" or a "text" language ... by default, "markup" languages (such as HTML, CSS, etc.) and plain text, etc., are considered "text", and programming languages such as C++, Java, PHP, etc., are considered "source".
"Source" languages will indent subsequent soft-wrapped lines (if the indent_subsequent_lines is true), whereas "text" languages will only indent up to the same level as the current line.
For each one you want to change, you'll need to edit the settings of the given language. #AdamAL's answer provides a great way to do this using the PackageResourceViewer package:
After install, do:
[Ctrl/Cmd]+[shift]+p, "Open Resource"
Find the name of the language you want to change, and find either the .sublime-syntax file or the .tmLanguage file. .sublime-syntax is supported from build 3084 of ST 3 and appears that it may trump values in the .tmLanguage file in supported versions, if present (when editing the definition of TaskPaper files provided by the "PlainTasks" package, my change didn't take when just editing the PlainTasks.tmLanguage, I had to edit the PlainTasks.sublime-syntax before it took).
In .sublime-syntax (which are YAML files) look for the first scope: line, where the main scope name of the language is identified (there will be lots of other scope: entries further down under contexts:).
In .tmLanguage (which are XML .plist files) look for the <string> following the <key>scopeName</key>.
Sublime Text Syntax Definition Documentation Reference:
scopeName
Name of the topmost scope for this syntax definition. Either source.<lang> or text.<lang>. Use source for programming languages and text for markup and everything else.
The <lang> (without brackets) is just an identifier string for the given syntax/language definition.
I noted that it seems that (in ST 3, anyway), no restart of Sublime Text is needed to get the changes to apply, if the edit is in the right place.
And also note that there may be other effects of changing this in more complex packages -- For example, in PlainTasks, the additional keybindings that it defines depended on it looking for a context that included text.todo, which I changed to source.todo in several places. So in order for the keybindings to work properly again, I also had to update my .sublime-keymap for that package. (This could also be because I changed it in a place besides the .sublime-syntax that I didn't need to. Just sayin' -- YMMV.)
Assuming a syntax highlighter uses a lexer to do the background work: when typing in an IDE with live syntax highlighting, does the lexer have to re-tokenize the entire file (in whatever language, ex. Java, C++, Python, etc), does the lexer only have to re-read and tokenize the current line, or does it only keep itself occupied with a single character/word at a time?
I'm asking because in a lot of editors/IDEs, most code remains the same as the programmer is typing, however, in some cases there's stuff like starting a string literal, which re-highlights the rest of the line, and in other cases like starting a multi-line comment, the whole text file becomes re-highlighted from the point where I start the multi-line comment, to the end of the file.
If the lexical analysis has to be done for the entire file for every single letter typed, wouldn't that make it slow, especially for larger (100.000+ lines) text files?
There is a syntax highlight and semantic highlight.
Syntax highlight is when editor only decorates based on language syntax - e.g. identifiers are black, keywords are pink and comments are green. Syntax highlight does not necessarily reparses (or, rather, tokenizes) the whole file - it can only tokenize "damaged region" (e.g. tokens around edit location). Of course, editor developer may opt to tokenize the whole input - as it is really fast, error-proof and easier to implement.
Semantic highlight (one that, for instance, can highlight global and local identifiers differently) usually require complete reparse - e.g. in Java adding "static" to function declaration would require you to invalidate function references both above and below the cursor. In some cases caching may be implemented (e.g. cache include files parse result as user edit does not change it that much). Semantic highlight is slow so it is usually combined with syntax highligh (you may see in Eclipse that the keywords are highlighted instantly - while member variable changes the color from the black after some small delay).
I didn't look this up, but I am pretty sure that it depends what is being highlighted. That is, comparing the local area you are typing in with basic syntax; versus, say an open comment that until closed highlights from that point until the end of the file.
I'm using an '&' symbol with HTML5 and UTF-8 in my site's <title>. Google shows the ampersand fine on its SERPs, as do all the browsers in their titles.
http://validator.w3.org is giving me this:
& did not start a character reference. (& probably should have been escaped as &.)
Do I really need to do &?
I'm not fussed about my pages validating for the sake of validating, but I'm curious to hear people's opinions on this and if it's important and why.
Yes. Just as the error said, in HTML, attributes are #PCDATA meaning they're parsed. This means you can use character entities in the attributes. Using & by itself is wrong and if not for lenient browsers and the fact that this is HTML not XHTML, would break the parsing. Just escape it as & and everything would be fine.
HTML5 allows you to leave it unescaped, but only when the data that follows does not look like a valid character reference. However, it's better just to escape all instances of this symbol than worry about which ones should be and which ones don't need to be.
Keep this point in mind; if you're not escaping & to &, it's bad enough for data that you create (where the code could very well be invalid), you might also not be escaping tag delimiters, which is a huge problem for user-submitted data, which could very well lead to HTML and script injection, cookie stealing and other exploits.
Please just escape your code. It will save you a lot of trouble in the future.
Validation aside, the fact remains that encoding certain characters is important to an HTML document so that it can render properly and safely as a web page.
Encoding & as & under all circumstances, for me, is an easier rule to live by, reducing the likelihood of errors and failures.
Compare the following: which is easier? Which is easier to bugger up?
Methodology 1
Write some content which includes ampersand characters.
Encode them all.
Methodology 2
(with a grain of salt, please ;) )
Write some content which includes ampersand characters.
On a case-by-case basis, look at each ampersand. Determine if:
It is isolated, and as such unambiguously an ampersand. eg. volt & amp > In that case don't bother encoding it.
It is not isolated, but you feel it is nonetheless unambiguous, as the resulting entity does not exist and will never exist since the entity list could never evolve. E.g., amp&volt >. In that case, don't bother encoding it.
It is not isolated, and ambiguous. E.g., volt& > Encode it.
??
HTML5 rules are different from HTML4. It's not required in HTML5 - unless the ampersand looks like it starts a parameter name. "©=2" is still a problem, for example, since © is the copyright symbol.
However it seems to me that it's harder work to decide to encode or not to encode depending on the following text. So the easiest path is probably to encode all the time.
I think this has turned into more of a question of "why follow the spec when browser's don't care." Here is my generalized answer:
Standards are not a "present" thing. They are a "future" thing. If we, as developers, follow web standards, then browser vendors are more likely to correctly implement those standards, and we move closer to a completely interoperable web, where CSS hacks, feature detection, and browser detection are not necessary. Where we don't have to figure out why our layouts break in a particular browser, or how to work around that.
Specifically, if HTML5 does not require using & in your specific situation, and you're using an HTML5 doctype (and also expecting your users to be using HTML5-compliant browsers), then there is no reason to do it.
Well, if it comes from user input then absolutely yes, for obvious reasons. Think if this very website didn't do it: the title of this question would show up as Do I really need to encode ‘&’ as ‘&’?
If it's just something like echo '<title>Dolce & Gabbana</title>'; then strictly speaking you don't have to. It would be better, but if you don't, no user will notice the difference.
Could you show us what your title actually is? When I submit
<!DOCTYPE html>
<html>
<title>Dolce & Gabbana</title>
<body>
<p>Am I allowed loose & mpersands?</p>
</body>
</html>
to http://validator.w3.org/ - explicitly asking it to use the experimental HTML 5 mode - it has no complaints about the &s...
In HTML, a & marks the begin of a reference, either of a character reference or of an entity reference. From that point on, the parser expects either a # denoting a character reference, or an entity name denoting an entity reference, both followed by a ;. That’s the normal behavior.
But if the reference name or just the reference opening & is followed by a white space or other delimiters like ", ', <, >, &, the ending ; and even a reference to represent a plain, & can be omitted:
<p title="&">foo & bar</p>
<p title="&">foo & bar</p>
<p title="&">foo & bar</p>
Only in these cases can the ending ; or even the reference itself be omitted (at least in HTML 4). I think HTML 5 requires the ending ;.
But the specification recommends to always use a reference like the character reference & or the entity reference & to avoid confusion:
Authors should use "&" (ASCII decimal 38) instead of "&" to avoid confusion with the beginning of a character reference (entity reference open delimiter). Authors should also use "&" in attribute values since character references are allowed within CDATA attribute values.
Update (March 2020): The W3C validator no longer complains about escaping URLs.
I was checking why image URLs need escaping and hence tried it in https://validator.w3.org. The explanation is pretty nice. It highlights that even URLs need to be escaped. [PS: I guess it will be unescaped when it's consumed since URLs need &. Can anyone clarify?]
<img alt="" src="foo?bar=qut&qux=fop" />
An entity reference was found in the document, but there is no
reference by that name defined. Often this is caused by misspelling
the reference name, unencoded ampersands, or by leaving off the
trailing semicolon (;). The most common cause of this error is
unencoded ampersands in URLs as described by the WDG in "Ampersands in
URLs". Entity references start with an ampersand (&) and end with a
semicolon (;). If you want to use a literal ampersand in your document
you must encode it as "&" (even inside URLs!). Be careful to end
entity references with a semicolon or your entity reference may get
interpreted in connection with the following text. Also keep in mind
that named entity references are case-sensitive; &Aelig; and æ
are different characters. If this error appears in some markup
generated by PHP's session handling code, this article has
explanations and solutions to your problem.
It depends on the likelihood of a semicolon ending up near your &, causing it to display something quite different.
For example, when dealing with input from users (say, if you include the user-provided subject of a forum post in your title tags), you never know where they might be putting random semicolons, and it might randomly display strange entities. So always escape in that situation.
For your own static HTML content, sure, you could skip it, but it's so trivial to include proper escaping, that there's no good reason to avoid it.
If the user passes it to you, or it will wind up in a URL, you need to escape it.
If it appears in static text on a page? All browsers will get this one right either way, and you don't worry much about it, since it will work.
Yes, you should try to serve valid code if possible.
Most browsers will silently correct this error, but there is a problem with relying on the error handling in the browsers. There is no standard for how to handle incorrect code, so it's up to each browser vendor to try to figure out what to do with each error, and the results may vary.
Some examples where browsers are likely to react differently is if you put elements inside a table but outside the table cells, or if you nest links inside each other.
For your specific example it's not likely to cause any problems, but error correction in the browser might for example cause the browser to change from standards compliant mode into quirks mode, which could make your layout break down completely.
So, you should correct errors like this in the code, if not for anything else so to keep the error list in the validator short, so that you can spot more serious problems.
A couple of years ago, we got a report that one of our web apps wasn't displaying correctly in Firefox. It turned out that the page contained a tag that looked like
<div style="..." ... style="...">
When faced with a repeated style attribute, Internet Explorer combines both of the styles, while Firefox only uses one of them, hence the different behavior. I changed the tag to
<div style="...; ..." ...>
and sure enough, it fixed the problem! The moral of the story is that browsers have more consistent handling of valid HTML than of invalid HTML. So, fix your damn markup already! (Or use HTML Tidy to fix it.)
If & is used in HTML then you should escape it.
If & is used in JavaScript strings, e.g., an alert('This & that'); or document.href, you don't need to use it.
If you're using document.write then you should use it, e.g. document.write(<p>this & that</p>).
If you're really talking about the static text
<title>Foo & Bar</title>
stored in some file on the hard disk and served directly by a server, then yes: it probably doesn't need to be escaped.
However, since there is very little HTML content nowadays that's completely static, I'll add the following disclaimer that assumes that the HTML content is generated from some other source (database content, user input, web service call result, legacy API result, ...):
If you don't escape a simple &, then chances are you also don't escape a & or a or <b> or <script src="http://attacker.com/evil.js"> or any other invalid text. That would mean that you are at best displaying your content wrongly and more likely are suspectible to XSS attacks.
In other words: when you're already checking and escaping the other more problematic cases, then there's almost no reason to leave the not-totally-broken-but-still-somewhat-fishy standalone-& unescaped.
The link has a fairly good example of when and why you may need to escape & to &
https://jsfiddle.net/vh2h7usk/1/
Interestingly, I had to escape the character in order to represent it properly in my answer here. If I were to use the built-in code sample option (from the answer panel), I can just type in & and it appears as it should. But if I were to manually use the <code></code> element, then I have to escape in order to represent it correctly :)
HI people
I recently changed to VIM for coding in C.
I'd like to hightlight the operators +-<=& ... etc
I searched in google how should i do it, and i found the answer in this website: I was suppose to do something like:
syntax match Operadores /[][><()&!|+*={}-]/
hi Operadores guifg=#000000 gui=BOLD
Those characters were supposed to appear as black, bold characters.
However, that doesn't happen when I open my .C files. However, if I create a newfile, (where there the C syntax doesn't show up), I am able to see the black, bolded operators.
How can i correct this situation, and why is this happening (it seams like if my syntax is beeing overwrided by the C syntax).
I'm using gvim, and this is my vimrc:
colorscheme nicotine
set smartindent
set number
set guifont=Inconsolata\ Medium\ 11
set numberwidth=5
noremap j jzz
noremap k kzz
Thanks, any help is appreciated.
(And dont forget I'm a novice in VIM, and ..sorry for my English)
The best way to do this is putting those two lines in the following file:
~/.vim/ftplugin/c.vim
creating it if it's not already present (of course you need to adjust the path to your personal Vim directory if you're not on un*x). That file is called for every C file you edit, and it's executed after the default scripts so your syntax won't be overridden.
For ftplugin to work you also have to add
filetype on
although a full
filetype plugin indent on
is usually more generally useful.