What is the difference in meaning between 'semantics' and 'syntax'? What are they?
Also, what's the difference between things like "semantic website vs. normal website", "semantic social networking vs. normal social networking" etc.
Syntax is the grammar. It describes the way to construct a correct sentence. For example, this water is triangular is syntactically correct.
Semantics relates to the meaning. this water is triangular does not mean anything, though the grammar is ok.
Talking about the semantic web has become trendy recently. The idea is to enhance the markup (structural with HTML) with additional data so computer could make sense of the web pages more easily.
Syntax is the grammar of a language - the rules by which to form sentences or expressions.
Semantics is the meaning you are trying to express with your code.
A program that is syntactically correct will compile and run.
A program that is semantically correct will actually do what you as the programmer intended it to do. i.e. it doesn't have any bugs in it.
Two programs written to perform the same task in different languages will use different syntaxes, but they would be the same semantically.
If you are talking about web (rather than programming languages):
The syntax of the language is whatever the browser (or processing program) can legally recognize and handle, and render to you. For example, your browser can render HTML, while your API can parse XML trees.
Semantics involve what is actually being represented. There's a lot of buzz now about semantic webs and all that stuff, but it essentially means that each entity is also associated with some human-readable information or metadata, so that a certain tag would have a supposed meaning and refer you to it.
Social networks are the same story. You put knowledge in the links
"An ant ate an aunt." has a correct syntax, but will not make sense semantically. A syntax is a set of rules that can be combined to produce infinite number of gramatically valid sentences, but few, very few of which has a semantics.
Syntax is the word order of a sentence. In English it would be the subject-verb-object form.
Semantic is the meaning behind words. E.g: she ate a saw. The word saw doesn't match according to the meaning of the sentence. but it is grammatically correct. so its syntax is correct. =)
Specifically, semantic social networking means embedding the actual social relationships within the page markup. The standard format for doing this as defined by microformats is XFN, XHTML Friends Network. In regards to the semantic web in general, microformats should be the go-to guide for defining embedded semantic content.
Semantic web sites use the concept of the semantic web, which aims to bring meaning to web content by using special annotations to identify certain concepts in a page. This makes possible the automatic (by a computer, not a human) reasoning about the content, which improves its aggregation, extraction, indexing and searching.
Explanations above are vague on the semantics side, semantics could mean the different elements at disposition to build arguments of value(these being comprehensible, to end-user man and digestible to the machine).
Of course this puts semantics and the programmer-editor-writer-communicator in the middle: he decides on the semantics that should be ideally defined to his public, comprehended by his public, general convention by his public and digestible to the machine-computer. Semantics should be agreed upon, are conceptual, must be implementable to both sides.
Say footnotes, inline and block-quotes, titles and on and on to end up into a well-defined and finite list. Mediawiki, wikitext as an example fails in that perspective, defining syntax for elements of semantic meaning left undefined, no finite list agreed upon. "meaning by form" as additional of what a title as an example again carries as textual content. Example "This is a title" becomes only semantics integrated by the supposition within agreed upon semantics, and there can be more then one set of say "This is important and will be detailed"
Asciidoc and pandoc markup is quite different in it's semantics, regardless of how each translates this by convention of syntax to output formats.
Programming, output formats as html, pdf, epub can have consequentially meaning by form, by semantics, the syntax having disappeared as a temporary tool of translation, and as one more consequence thus the output can be scanned robotically for meaning, the champ of algorithms of 'grep': Google. Looking for the meaning of "what" in "What is it that is looked for" based upon whether a title or a footnote, or a link is considered.
Semantics, and there can be more then one layer, even the textual message carries (Chomsky) semantics thus could be translated as meaning by form, creating functional differences to anything else in the output chain, including a human being, the reader.
As a conclusion, programmers and academics should be integrated, no academic should be without knowledge of his tools, as any bread and butter carpenter. Programmers should be academics in the sense that the other end of the bridging they accomplish is the end user, the bridge... much so: semantics.
m.
Related
I was reading a article about it, and there was a line in that article which confused me a bit:
".....the markup language is used to present information whereas programming language is used to give instructions to a computer to perform a particular task."
The Computer still has to follow instructions of markup language to display information on the screen, right?
Please help! And Thank you!
You are right and the article is also right, but there's a bit of clarification.
A markup language (HTML, XAML, markdown, etc.) is an example of a declarative language, which says "this is what the result should be (e.g. what the screen should look like, what bit of input or output is expected, and so on). Declarative languages do not say anything about how to do something, but ultimately rely on an "engine" that imperatively gets to the results.
In contrast an imperative language describes each step that must be taken to achieve the end result (i.e. an algorithm). This is a set of instructions.
The reason your statement, "The Computer still has to follow instructions of markup language to display information on the screen" is correct is because a declarative language must rely on imperative operators and statements such as conditionals, looping, and so on (imperative) at a lower level to achieve the stated declarations.
Incidentally, referring back to your title... both are programming languages. They're just using different paradigms.
The docs of File.exist? says:
Return true if the named file exists.
Note that last word used; "exists". This is correct. "File exist" without the ending s is not correct.
The method File.exists? exists, but they deprecated this method. I am thinking it should have been the other way around. What am I missing?
Also, it's noteworthy that other languages/libraries use exists, for example Java and .NET.
Similarly, "this equals that" - but Ruby uses equal, again dropping the ending s. I am getting a feeling that Ruby is actively walking in another direction than mainstream. But then there has to be a reason?
This is largely a subjective call. Do you read the call as "Does this file exist?" or "File exists"? Both readings have their merits.
Historically Ruby has had a lot of aliased methods like size vs. length, but lately it seems like the core team is trying to focus on singular, consistent conventions that apply more broadly.
You'd have to look closely at the conversations on the internal mailing list surrounding the decisions here. I can't find them easily, only people dealing with the changes as deprecation warnings pop up.
The Ruby core team is a mix of people who speak different languages but the native language is Japanese, so perhaps that's guiding some of these decisions. It could be a preference to avoid odd inflections on verbs.
I agree that if File.exists?('x.txt') reads much more natural than the plural form, which was probably Matz's intention for the alias. As far as I'm concerned, this particular deprecation was misguided.
However the general preference of a plural form may well be routed in handling enumarables/collections, where plural makes a sense when used with idioms like this:
pathnames.select(&:exist?)
exist? matches the convention used elsewhere throughout the stdlib, and goes back to the early days of ruby. For example array.include? (not includes?), string.match? (not matches?), object.respond_to? (not responds_to?). So in this light, File.exists? was always a blemish.
Some recommend that you read the dot as "does". So "if file does exist," "if array does include," "if string does match," etc.
I just discovered OWL and Protege. Upon reading through this reference page (which I quote below), I am left wondering whether it is possible to not use the abstract OWL syntax, and rather to write in DL syntax. My background is in logic, so it sounds like it would be more fun even if I would have to translate the ontologies later (though I am sure there must be applications to do this--besides, don't reasoners use DL?).
If it is possible, what configuration of settings should I use in Protege (or other software of your suggestion) in order to do this? I suspect it's not possible, but I want to be sure, as I see no good reason for this other than the awkwardness of special symbols.
EDIT: If it is NOT possible, how exactly are DL languages used?
OWL DL is the description logic SHOIN with support of data values, data types
and datatype properties, i.e., SHOIN(D), but since OWL is based on RDF(S), the
terminology slightly differs. ... For description of OWL ontology or knowledge
base, the DL syntax can be used. There is an "abstract" LISP-like syntax
defined that is easier to write in ASCII character set.
Here's a very brief working example of the two syntax styles for the same data.
don't reasoners use DL?
Not necessarily. They use all kinds of logics, some of which are DLs, some are not.
If it is possible, what configuration of settings should I use in Protege (or other software of your suggestion) in order to do this?
I'm pretty sure there is no such pluggin for Protégé. But if you really want some fun, use a text editor and write your ontology by hand. There are many syntaxes you can use: the functional syntax, the OWL/XML syntax, the RDF/XML syntax are all normative. In addition, you can use the Manchester syntax, Turtle, N-Triples, JSON-LD, that will be future recommendations for writing RDF (and therefore OWL). Or the more exotic RDF/JSON, HDT. Or again, more "powerful" syntaxes like Notation3, TriG, TriX, NQuads. Plenty of fun!
In any case, if you would like to write in the DL syntax, you would need to use special Unicode characters or special commands like in LaTeX for instance. And the parser that deals with it would have to read those characters or commands. Not ideal if you are programming. But you can always use the DL syntax in your writings.
BTW, the current standard Web Ontology Language is OWL 2. Its DL variant (viz., OWL 2 DL) is based on the even more irresistible SROIQ.
I worked on different projects in different countries and remarked that sometimes the code became internationalized, like
SetLargeurEtHauteur() (for SetWidthAndHeight, fr)
Dim _ListaDeObiecte as List(Of Object) (for _ObjectList, ro)
internal void SohranenieUserov() (for SaveUsers, ru)
etc.
It happens that in countries with Latin alphabet this mix is more pronounced, because there is no need of transliteration.
More than that, often the programming "jargon" is inspired by the project specifications language. There are cases that terms in "project language" have a meaning that is not "translatable" in English.
There are also projects on which works only, say a French team, uses French words (say, Personne, Vehicule, Projet etc).
In that cases I personally add in specifications a "Dictionary" that explains all business object names and only these objects are used in other (French) language.
Say:
Collectif - ensemble des Personnes;
All the actions(Get, Set, Update, Modify, Load, etc) are in English.
Now that "strong" names could be used in code:
AddPersonneToCollectif.
What is your approach to "internationalization"?
PS.
I was amused that VisualStudio compiles and runs projects in .NET with buttons named à la "btnAddÉlève" or "кпкСтоп"...
My personal approach, which is shared by many but not all in the programming community, is that source code should be in English and, if possible, all the development tools should be in English too.
The most important reason for this is being able to share your problems and solutions with the world (like we are doing now in StackOverflow, no less) without having to translate class names, error messages, paths and other artifacts every time.
It also helps consistency, because most libraries are written in English and having element names that mix two languages doesn't really help anyone, besides being a constant focus of internal conflicts when a verb like Add isn't always traslated.
English code also makes it easier to add foreign people to a project without worrying about comprehension and misunderstandings (especially between closely related languages, like Spanish and Portuguese, which have lots of false cognates)
A good link on this subject: http://www.codinghorror.com/blog/2009/03/the-ugly-american-programmer.html
(In case anyone wonders, I'm south-american and English is not my primary language)
Even if everyone on the team is a good English speaker (which is not a given), they may not necessarily know the English equivalent of all the business terminology.
I think it's a project-specific decision what to allow, but I would generally tolerate and in some cases encourage business terms (e.g. entity names) in the local language, but not technical terms (i.e. not Largeur/Hauteur instead of Width/Height).
For example in the financial world in France, everyone knows what is meant by OPCVM and FCP - if you attempt English translations you might end up with more misunderstandings than you do by allowing mixed languages.
I have the same issue with Norwegian currently. I guess it depends on your position in the project, the available time and the role of the software.
In my case, I have decided to keep all terms in an existing protocol and library I am working with in Norwegian, as I can reasonably expect that generations of administrative workers have gotten used to these, and since the library depends on the protocol. In a library wrapper for an international project, I have translated each method name literally, and added an English language documentation of the method.
Comments and documentation on the code are in English.
If designing a software from scratch, I would try to find English terms for all method names and even business terms (if reasonable. I can hardly think of an example where no term can be found though.), to keep it "portable".
If you're writing code that you may be used internationally one day, write it in English. In doubt, write it in English, even comments if you can (although I suppose you can add a few comments in the language of your workplace).
It's not specific to coding unfortunately. English isn't my native language, but I've been able to read a number of technical papers and participate to international conferences with people from all over the world. These collaborations simply wouldn't work if everyone published in their respective native languages.
It may be sad if you feel like defending your language at all cost, but you have to be realistic about it. I suppose English has the advantage to be relatively simple for achieving a basic level: no genders for names, no conjugations, no cases.
Generally code referring to language concepts should be in the same mother language as the programming language (i.e. English - for, while, string are all English words).
It's OK (but not great) to have variables and domain concepts in a local language, but you definitely don't want to be translating List, Object, Decimal, etc. into terms which cause programmers more work in reconciling two languages. Even still, I would strongly lobby to restrict very common domain concepts like Collection, Membership, Person, User and possibly less common domain concepts like Invoice, Receipt to English where this is possible.
It would be like coding half your classes in VB and half in C# - your brain has to make a cognitive shift. While this is good for hybrid apps (JavaScript on the web and C# on the backend) because it helps you keep what's running where clear, it isn't good for a general programming.
In addition, using English for everything makes the domain and language words work together better.
There are always exceptions. There are certain cases where you would use a native word anyway - where the word describes the domain best. For instance, in our (English) code base, we had references to Mexican Spanish terms for certain concepts which were only relevant for people running our software in Mexico. Typically, Japanese terms were spelled out phonetically/Romaji, though - it was difficult for non-Japanese to be able to pronounce the pictograms ;-).
I think I'd call a code base like that "abysmal" rather than "internationalized", but the general rule I've always heard is that if you ever think that someone other than one who speaks your language might ever touch the code, do it in english.
I think that good design guideline is to write code with use of English names and with english comments only (of course if your team is capable to do this, but in case of international team English seems to be natural choose, since it's a most popular language, expecially in IT world).
Good explanation of such guidline is that keywords in most of programming languages are taken from English so writing your code using English names gives more consistent look and thanks to this you end with code that is easier to read.
Another reason is that most of compilers can handle only ascii characters as names of classes, methods, etc. so probably you will end with some strange names when you decide to use some language with alphabet containing non ascii chars.
Third reason that came to my mind is sharing your code on site like SO. Today I opened a post with a piece of code where classes had Spanish names. It was hard for me to guess what was the purpose of this class (even if sometimes is not necessary it is good when you read code and understand all used words:)).
To sum up I think that internationalization of code is not a good idea. You can imagine that keywords in programming languages (e.g. class, try, while) could also be localized and probably you can imagine also how hard life could be then...
To keep things consistent, I would make the code the same (human) language as the (programming) language. That is, if the programming language uses English keywords (like for, switch, public, etc) then keep the rest of the code in English. If you are using a compiler that recognizes (say) the Swahili translations of keywords, then keep the rest of the code in Swahili.
Many APIs have standardized naming schemes that are followed regardless of (human) language, and the accompanying documentation is translated as needed (instead of the source code).
No matter what (human) language you choose, pick one and stick with it. I'd much rather try to wade through source code in German than code that was a mix of German and English.
I am writing a coding standards document for a team of about 15 developers with a project load of between 10 and 15 projects a year. Amongst other sections (which I may post here as I get to them) I am writing a section on code formatting. So to start with, I think it is wise that, for whatever reason, we establish some basic, consistent code formatting/naming standards.
I've looked at roughly 10 projects written over the last 3 years from this team and I'm, obviously, finding a pretty wide range of styles. Contractors come in and out and at times, and sometimes even double the team size.
I am looking for a few suggestions for code formatting and naming standards that have really paid off ... but that can also really be justified. I think consistency and shared-patterns go a long way to making the code more maintainable ... but, are there other things I ought to consider when defining said standards?
How do you lineup parenthesis? Do you follow the same parenthesis guidelines when dealing with classes, methods, try catch blocks, switch statements, if else blocks, etc.
Do you line up fields on a column? Do you notate/prefix private variables with an underscore? Do you follow any naming conventions to make it easier to find particulars in a file? How do you order the members of your class?
What about suggestions for namespaces, packaging or source code folder/organization standards? I tend to start with something like:
<com|org|...>.<company>.<app>.<layer>.<function>.ClassName
I'm curious to see if there are other, more accepted, practices than what I am accustomed to -- before I venture off dictating these standards. Links to standards already published online would be great too -- even though I've done a bit of that already.
First find a automated code-formatter that works with your language. Reason: Whatever the document says, people will inevitably break the rules. It's much easier to run code through a formatter than to nit-pick in a code review.
If you're using a language with an existing standard (e.g. Java, C#), it's easiest to use it, or at least start with it as a first draft. Sun put a lot of thought into their formatting rules; you might as well take advantage of it.
In any case, remember that much research has shown that varying things like brace position and whitespace use has no measurable effect on productivity or understandability or prevalence of bugs. Just having any standard is the key.
Coming from the automotive industry, here's a few style standards used for concrete reasons:
Always used braces in control structures, and place them on separate lines. This eliminates problems with people adding code and including it or not including it mistakenly inside a control structure.
if(...)
{
}
All switches/selects have a default case. The default case logs an error if it's not a valid path.
For the same reason as above, any if...elseif... control structures MUST end with a default else that also logs an error if it's not a valid path. A single if statement does not require this.
In the occasional case where a loop or control structure is intentionally empty, a semicolon is always placed within to indicate that this is intentional.
while(stillwaiting())
{
;
}
Naming standards have very different styles for typedefs, defined constants, module global variables, etc. Variable names include type. You can look at the name and have a good idea of what module it pertains to, its scope, and type. This makes it easy to detect errors related to types, etc.
There are others, but these are the top off my head.
-Adam
I'm going to second Jason's suggestion.
I just completed a standards document for a team of 10-12 that work mostly in perl. The document says to use "perltidy-like indentation for complex data structures." We also provided everyone with example perltidy settings that would clean up their code to meet this standard. It was very clear and very much industry-standard for the language so we had great buyoff on it by the team.
When setting out to write this document, I asked around for some examples of great code in our repository and googled a bit to find other standards documents that smarter architects than I to construct a template. It was tough being concise and pragmatic without crossing into micro-manager territory but very much worth it; having any standard is indeed key.
Hope it works out!
It obviously varies depending on languages and technologies. By the look of your example name space I am going to guess java, in which case http://java.sun.com/docs/codeconv/ is a really good place to start. You might also want to look at something like maven's standard directory structure which will make all your projects look similar.