Re: [whatwg] Physical quantities: var or i?
2012-01-21 0:30, Ian Hickson wrote: On Tue, 26 Jul 2011, Jukka K. Korpela wrote: [...] I don’t think you have clarified whether var is suitable for physical quantities, but I guess you meant to imply it—even though there is not a single example about markup for physical quantities. Given that the spec contains the exact example you gave (E=mc^2), and given that the definition explicitly includes an identifier representing a constant as one of the uses for the element, I have to disagree with your assessment. Now that you have added that example, the text implies that var is the suggested markup for symbols of physical quantities. It is still somewhat odd that this is expressed via an example only, and the basic prose says: “The var element represents a variable. This could be an actual variable in a mathematical expression or programming context, an identifier representing a constant, a function parameter, or just be a term used as a placeholder in prose.” None of the examples covers symbols of physical quantities, and yet they are probably more common texts in general (as opposite to mathematics and programming) than the examples given. On the other hand, it seems that it doesn’t really matter. The var element has now been defined to have such a wide and vague meaning that it is pointless to use it. There is little reason to expect that any software will ever pay attention to var markup on any semantic basis. You seem to imply that there was reason to expect so before, which is certainly news to me! I have rather been optimistic about future developments for markup elements that have been defined exactly enough to warrant meaningful semantics-based processing. For example, most of the uses mentioned in current text imply that var element contents should be kept intact in automatic language translation. I would not really expect these elements to be used for anything other than styling hooks. That might be realistic, especially there is no significant semantic clarification in sight in general. This raises the question why we could not just return to the original design with some physical markup like i, b, and u together with span that was added later. What’s the idea of wasting time in wondering which markup to choose, among several vaguely described alternatives, when it all ends up with being comparable to arbitrary author-named styles in word processing? The advantage of using i, b, and u is that they have defined default rendering (even in the absense of CSS) and universal support in browsers. Authors can still use classes if they like, and they can still change the rendering via CSS just as they can when some fancy markup is used. So authors will use i if they think italics is semantically essential, and var won’t be used much. That seems to be the status quo. So why not simply define i recommended and describe var, cite, em, and dfn as deprecated but supported alternatives? This would make authoring simpler without any real cost. There’s little reason to tell authors to use “semantic markup” if we don’t think it has real effect on anything. However, some authors like the ease of maintenance that comes from using elements as a general classification mechanism and classes to provide fine-grained control, and it is mostly for them that HTML provides a variety of more specific elements like var. This implies a burden on learning, teaching, and using HTML. Anyone who seriously tries to understand HTML will ask, for example, which of var, cite, em, dfn, i, span, abbr he should use in particular situations. Authors who wish to use classification may well do that with elements like i as well. Then they just need to decide on their own classification. Too bad there's no example ofvar used in programming context. The current wording suggests that it would be normal, when discussing programming, to write, say, Then we define the variable varmyFoo/var of type codefooType/code with initial value codeFoo/code - -, which really makes no sense, even if we use both var and code for myFoo. Why does it make no sense? Because var does not imply that the contents is computer code. Yet a variable name in programming is surely code if a type name or a literal is. And using codevarmyFoo/var/code is clumsy, and it makes the text appear in italics by default, which is probably unsuitable (monospace italics doesn’t work well). Why would an author use markup that by default causes rendering that he does *not* want, when there’s the option of using span? Because it implies that in default rendering, identifiers of variables appear in italics whereas identifiers of types or classes do not. Why would anyone use extra var markup when it has no other implications than requiring extra CSS code to remove (when possible) italics? To enable easier maintenance of the markup and easy self-documenting styling, same as pretty much all of HTML.
Re: [whatwg] Physical quantities: var or i?
On Tue, 26 Jul 2011, Jukka K. Korpela wrote: 25.07.2011 22:02, Ian Hickson wrote: So what markup should we use for E = mc�, given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? It sounds like you want to use these characters: U+1D438 MATHEMATICAL ITALIC CAPITAL E U+1D45A MATHEMATICAL ITALIC SMALL M U+1D450 MATHEMATICAL ITALIC SMALL C No, I don’t want to use them, since only about one person in a million would see the expression. There are several reasons to that, including the absence of those characters in fonts—the only commonly available font that contained a reasonable collection of Plane 1 characters was code2001, and it does not seem to be distributed by its author any more. Well, any new feature will take time to get adopted. We live in the future here. That it doesn't work yet isn't a valid argument against it. :-) Comparing this with how well iE/i = im/iic/i² works, I don't think anyone who understands the implications will give a second though to using such Plane 1 characters in HTML documents. If it works well, I think we're good. Problem solved. Alternatively, you can use MathML to mark up the equation. Or I could use LaTeX and get a presentation of acceptable quality. Or an image, as people still widely use. The question was about markup of physical quantities in HTML. Using other tools just to present a casual equation in running text would be disproportionate. MathML is merely one of several options available to HTML authors that I was enumerating. It is obviously not the only one. For more complicated cases, it may be the preferred option (e.g. if you have fractions, calculus, etc). For simpler cases, e.g. a single variable, it's obviously not simpler than just using var. Whether you want something in italics or not is more a matter for CSS than a matter for HTML. In many contexts, by long traditions and conventions, the use of italics is a matter of content, not casual presentation. Well, kinda. The content is variable, or planck constant, or pi; the presentation as a set of pixels representing an italics /i/ vs an audio sample that says eye vs a set of raised dots in Nemeth Braille is the presentational aspect. As such I think it's fair to say that the italics is a mapping of the var semantic to display presentation via CSS. Should we consider the var element as covering physical quantities too? After all, they can be regarded as variables in a broad sense, as symbols that denote different values in different situations. However, varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. You can look at it as being a variable whose value is a constant of nature. I've clarified the spec to indicate that this is fine. I don’t think you have clarified whether var is suitable for physical quantities, but I guess you meant to imply it—even though there is not a single example about markup for physical quantities. Given that the spec contains the exact example you gave (E=mc^2), and given that the definition explicitly includes an identifier representing a constant as one of the uses for the element, I have to disagree with your assessment. On the other hand, it seems that it doesn’t really matter. The var element has now been defined to have such a wide and vague meaning that it is pointless to use it. There is little reason to expect that any software will ever pay attention to var markup on any semantic basis. You seem to imply that there was reason to expect so before, which is certainly news to me! I would not really expect these elements to be used for anything other than styling hooks. So authors will use i if they think italics is semantically essential, and var won’t be used much. That seems to be the status quo. A programming language variable is something that is _not_ conventionally rendered in italics. Rather, they are usually (though for no really good reason) rendered in a monospace font, like any other expressions in computer languages. Indeed. And vectors are usually bold. So why should authors be told to use markup that by default (and always when CSS is off) results in programming language constructs to be italicized? Flagging “placeholders” with italics (as in “issue the command kbdrm ifilename/i/kbd to delete a file) is a widely used and understood style, but programming language variables are a completely different issue. Well it's entirely up to the authors, of course; if they would rather only use divs and spans then there's not much we can do to stop them. However, some authors like the ease of maintenance that comes from using elements as a general classification mechanism and classes to provide fine-grained control, and it is mostly for them that HTML provides a variety
Re: [whatwg] Physical quantities: var or i?
25.07.2011 22:02, Ian Hickson wrote: So what markup should we use for E = mc�, given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? It sounds like you want to use these characters: U+1D438 MATHEMATICAL ITALIC CAPITAL E U+1D45A MATHEMATICAL ITALIC SMALL M U+1D450 MATHEMATICAL ITALIC SMALL C No, I don’t want to use them, since only about one person in a million would see the expression. There are several reasons to that, including the absence of those characters in fonts—the only commonly available font that contained a reasonable collection of Plane 1 characters was code2001, and it does not seem to be distributed by its author any more. Characters not supported by any of the fonts installed in the user’s system don’t degrade well. The user sees a small box or the ”�” character (which may appear due to other problems, too). Comparing this with how well iE/i = im/iic/i² works, I don’t think anyone who understands the implications will give a second though to using such Plane 1 characters in HTML documents. Alternatively, you can use MathML to mark up the equation. Or I could use LaTeX and get a presentation of acceptable quality. Or an image, as people still widely use. The question was about markup of physical quantities in HTML. Using other tools just to present a casual equation in running text would be disproportionate. Whether you want something in italics or not is more a matter for CSS than a matter for HTML. In many contexts, by long traditions and conventions, the use of italics is a matter of content, not casual presentation. When people know they cannot use italics, they are forced to simulating it (e.g., writing /a/ to denote italic “a”) or to avoiding the issue with clumsy methods like long prose explanations. Wouldn’t it be odd to pretend that in HTML, you are forced to something like that? After all, i has been with us since the dawn of HTML, and all browsers support it when they can use italics at all (and may use some special representation when not). Should we consider the var element as covering physical quantities too? After all, they can be regarded as variables in a broad sense, as symbols that denote different values in different situations. However, varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. You can look at it as being a variable whose value is a constant of nature. I've clarified the spec to indicate that this is fine. I don’t think you have clarified whether var is suitable for physical quantities, but I guess you meant to imply it—even though there is not a single example about markup for physical quantities. On the other hand, it seems that it doesn’t really matter. The var element has now been defined to have such a wide and vague meaning that it is pointless to use it. There is little reason to expect that any software will ever pay attention to var markup on any semantic basis. So authors will use i if they think italics is semantically essential, and var won’t be used much. A programming language variable is something that is _not_ conventionally rendered in italics. Rather, they are usually (though for no really good reason) rendered in a monospace font, like any other expressions in computer languages. Indeed. And vectors are usually bold. So why should authors be told to use markup that by default (and always when CSS is off) results in programming language constructs to be italicized? Flagging “placeholders” with italics (as in “issue the command kbdrm ifilename/i/kbd to delete a file) is a widely used and understood style, but programming language variables are a completely different issue. Too bad there's no example ofvar used in programming context. The current wording suggests that it would be normal, when discussing programming, to write, say, Then we define the variable varmyFoo/var of typecodefooType/code with initial value codeFoo/code - -, which really makes no sense, even if we use bothvar andcode for myFoo. Why does it make no sense? Because it implies that in default rendering, identifiers of variables appear in italics whereas identifiers of types or classes do not. Why would anyone use extra var markup when it has no other implications than requiring extra CSS code to remove (when possible) italics? -- Yucca, http://www.cs.tut.fi/~jkorpela/
Re: [whatwg] Physical quantities: var or i?
On Thu, 14 Apr 2011, Jukka K. Korpela wrote: Looking at the nice summary (with examples) of text-level markup at http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#usage-summary I started wondering why there is no example of markup for symbols of physical quantities. The descriptions of individual elements or their examples don't seem to say anything about this either. The main reason is that most of these symbols have Unicode characters and don't need special markup. So what markup should we use for E = mc�, given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? It sounds like you want to use these characters: U+1D438 MATHEMATICAL ITALIC CAPITAL E U+1D45A MATHEMATICAL ITALIC SMALL M U+1D450 MATHEMATICAL ITALIC SMALL C Alternatively, you can use MathML to mark up the equation. Physical quantities surely satisfy the requirement that typical typographic presentation is italicized in the following, and they are to be offset from the normal prose, but why aren't they mentioned in the fairly long list of examples then: The i element represents a span of text in an alternate voice or mood, or otherwise offset from the normal prose, such as a taxonomic designation, a technical term, an idiomatic phrase from another language, a thought, a ship name in Western texts, or some other prose whose typical typographic presentation is italicized. http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-i-element (As an aside, the wording a taxonomic designation is too broad, as by biological nomenclature rules, genus and species names are to be italiced but higher taxons, e.g. family names, like Canidae, must not. Besides, e.g. an English name of a species is taxonomic too... So scientific names of organisms would be a better formulation.) Whether you want something in italics or not is more a matter for CSS than a matter for HTML. Should we consider the var element as covering physical quantities too? After all, they can be regarded as variables in a broad sense, as symbols that denote different values in different situations. However, varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. You can look at it as being a variable whose value is a constant of nature. I've clarified the spec to indicate that this is fine. On Thu, 14 Apr 2011, Bjartur Thorlacius wrote: Well, a constant isn't really variable any more, is it? I thought var was meant to mark up text that couldn't simply be 'copypasted' without filling in the unknowns (free variables). Defined variables (whether in source code or formulae) do not conform to that definition. So, coderm -r var$path/var/code would conform (as a reply to the question how does one remove a (potentially non-empty) directory on *nix?) as $path is undefined, but codevari/var++/code would not, as i isn't ment to be substituted. What do you base this interpretation on? On Sat, 16 Apr 2011, Jukka K. Korpela wrote: Besides, there is no implied uniform rendering for variables in the current broad meaning for var. In mathematics, variables are conventionally written in italics. But the HTML(5) notion of variable is wider: The var element represents a variable. This could be an actual variable in a mathematical expression or programming context, or it could just be a term used as a placeholder in prose. A programming language variable is something that is _not_ conventionally rendered in italics. Rather, they are usually (though for no really good reason) rendered in a monospace font, like any other expressions in computer languages. Indeed. And vectors are usually bold. This is the kind of thing I would expect to see handled using classes, e.g.: var class=vectora/var #x2A2F; var class=vectorb/var = vara/var varb/var sin vartheta;/var var class=vectorn/var Too bad there's no example of var used in programming context. The current wording suggests that it would be normal, when discussing programming, to write, say, Then we define the variable varmyFoo/var of type codefooType/code with initial value codeFoo/code - -, which really makes no sense, even if we use both var and code for myFoo. Why does it make no sense? -- Ian Hickson U+1047E)\._.,--,'``.fL http://ln.hixie.ch/ U+263A/, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Re: [whatwg] Physical quantities: var or i?
Aryeh Gregor wrote: So what markup should we use for E = mc², given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? Those three characters are typeset, read, and otherwise presented identically to variables, so the correct tag is var. Perhaps the spec could be clearer on this point. So do yo mean that everything that is rendered identically to (some assumed rendering of) variables should be marked up as var? If you imply that variables are rendered in italics, then apparently ship names, scientific names of organisms, and gene symbols call for var, too, right? Seriously speaking, if all that we can say about some notations is that they are, by convention, rendered in italics if possible, then surely i is correct, if the notation does not clearly fall into a category for which there is semantic markup element defined. Besides, there is no implied uniform rendering for variables in the current broad meaning for var. In mathematics, variables are conventionally written in italics. But the HTML(5) notion of variable is wider: The var element represents a variable. This could be an actual variable in a mathematical expression or programming context, or it could just be a term used as a placeholder in prose. A programming language variable is something that is _not_ conventionally rendered in italics. Rather, they are usually (though for no really good reason) rendered in a monospace font, like any other expressions in computer languages. Too bad there's no example of var used in programming context. The current wording suggests that it would be normal, when discussing programming, to write, say, Then we define the variable varmyFoo/var of type codefooType/code with initial value codeFoo/code - -, which really makes no sense, even if we use both var and code for myFoo. I suppose what the wording really _means_ is something like This could be a variable in a mathematical expression or a placeholder as used especially in technical and scientific language. The HTML 4.01 mentions program argument, but this could be misleading too, as it does not really refer to actual arguments (as in the program invocation latex mydoc.tex) but to placeholders for them (as in the instruction then process the document by issuing the command codelatex varfilename/var/code). An example of using placeholders in humanities might be The normal word order in this language is varsubject/var varobject/var varverb/var. Clarified that way, var would refer to notations that are normally rendered in italics - but it would of course not refer to _any_ notation that is normally rendered in italics. In this perspective, my original question really boils down to the question whether symbols of physical quantities should be regarded as placeholders. I have no strong feelings in either direction. I'd just like to see the question settled one way or another, at least by giving an example of using var or, as the case may be, i for such a quantity. -- Yucca, http://www.cs.tut.fi/~jkorpela/
Re: [whatwg] Physical quantities: var or i?
On Thu, Apr 14, 2011 at 10:02 AM, Jukka K. Korpela jkorp...@cs.tut.fi wrote: Looking at the nice summary (with examples) of text-level markup at http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#usage-summary I started wondering why there is no example of markup for symbols of physical quantities. The descriptions of individual elements or their examples don't seem to say anything about this either. So what markup should we use for E = mc², given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? Those three characters are typeset, read, and otherwise presented identically to variables, so the correct tag is var. Perhaps the spec could be clearer on this point.
[whatwg] Physical quantities: var or i?
Looking at the nice summary (with examples) of text-level markup at http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#usage-summary I started wondering why there is no example of markup for symbols of physical quantities. The descriptions of individual elements or their examples don't seem to say anything about this either. So what markup should we use for E = mc², given that by the applicable standards, E, M, and c should appear in italics and the other characters as normal (upright)? Physical quantities surely satisfy the requirement that typical typographic presentation is italicized in the following, and they are to be offset from the normal prose, but why aren't they mentioned in the fairly long list of examples then: The i element represents a span of text in an alternate voice or mood, or otherwise offset from the normal prose, such as a taxonomic designation, a technical term, an idiomatic phrase from another language, a thought, a ship name in Western texts, or some other prose whose typical typographic presentation is italicized. http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-i-element (As an aside, the wording a taxonomic designation is too broad, as by biological nomenclature rules, genus and species names are to be italiced but higher taxons, e.g. family names, like Canidae, must not. Besides, e.g. an English name of a species is taxonomic too... So scientific names of organisms would be a better formulation.) But the i element should obviously be used in the absence of a more semantic element; e.g., not for expressions that fall into the scope of use of the cite element. Should we consider the var element as covering physical quantities too? After all, they can be regarded as variables in a broad sense, as symbols that denote different values in different situations. However, varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. So I would guess that iE/i = im/iic/i² is the way to go. I think an example like this, or the addition of physical quantities into the list of examples, or both, would be the semantics and intended use of elements somewhat clearer. -- Yucca, http://www.cs.tut.fi/~jkorpela/
Re: [whatwg] Physical quantities: var or i?
Jukka K. Korpela: varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. It would not, ‘c’ is merely a variable with constant value. varE/var = varm/var·varc/varsup2/sup Or math, eventually.
Re: [whatwg] Physical quantities: var or i?
On 4/14/11, Christoph Päper christoph.pae...@crissov.de wrote: Jukka K. Korpela: varc/var would be odd, wouldn't it, since the symbol denotes a universal constant of nature. It would not, ‘c’ is merely a variable with constant value. Well, a constant isn't really variable any more, is it? I thought var was meant to mark up text that couldn't simply be 'copypasted' without filling in the unknowns (free variables). Defined variables (whether in source code or formulae) do not conform to that definition. So, coderm -r var$path/var/code would conform (as a reply to the question how does one remove a (potentially non-empty) directory on *nix?) as $path is undefined, but codevari/var++/code would not, as i isn't ment to be substituted. varE/var = varm/var·varc/varsup2/sup Or math, eventually. Or, in the meantime, code (IMHO, at least). It's not source code for a computer program, but for all purposes and intentions I can think of, source code and formulae can be treated equivalently. The spec formally requires 'computer code,' i.e. sth understood by a computer, making my suggested usage non-conformant.
