For educational purposes, I would like to build an IDE for PHP coding.
I made a form app and added OpenFileDialog ..(my c# knowledge was useful, because it was easy ... even though without intelisense!)
Loading a file and reading lines from it is basically the same in every language (even PERL).
But my goal is to write homemade intelisense. I don't need info on the richtextBox and the events it generates, endline, EOF, etc, etc.
The problem I have is, how do I handle the data? line for line?
a struct for each line of text file?
looping all the structs in a linked list? ...
while updating the richtextBox?
searching for opening and closing brackets, variables, etc, etc
I think Microsoft stores a SQL type of database in the app project folders.
But how would you keep track of the variables and simulate them in some sort of form?
I would like to know how to handle this efficiently on dynamic text.
Having never thought this through before, it sounds like an interesting challenge.
Personally, I think you'll have to implement a lexical scanner, tokenizing the entire source file into a source tree, with each token also having information about it mapping the token to a line/character inside of the source file.
From there you can see how far you want to go with it - when someone hovers over a token, it can use the context of the code around it to be more intelligent about the "intellisense" you are providing.
Hovering over something would map back to your source tree, which (as you are building it) you would load up with any information that you want to display.
Maybe it's overkill, but it sounds like a fun project.
This sounds to be related to this question:
https://softwareengineering.stackexchange.com/questions/189471/how-do-ide-s-provide-auto-completion-instant-error-checking-and-debugging
The accepted answer of that question recommends this link which I found very interesting:
http://msdn.microsoft.com/en-us/magazine/cc163781.aspx
In a nutshell, most IDEs generate the parse tree from the code and that is what they stores and manage.
Related
I can't seem to find the answer, how do you create a new file in Ocaml? Do you edit your file in the terminal? Where does the source code appear?
I think you're asking how to write code in OCaml, i.e., how to create an OCaml source file. (This isn't completely clear. You could be asking how to write OCaml code that creates a file.)
The details of creating OCaml source depend on your development environment, not on the language itself. So there is no one answer.
The general answer is that you can use any tool you like that knows how to create a text file. If you like working from the command line (as I do) you can work in a terminal environment and run some kind of vintage text editor from the last millennium (as I do). If you like a GUI environment, you can run some kind of "programmer's editor" from the current millennium, or really any kind of editor that creates basic utf-8 files (or even ASCII files).
Generally the editor will have to be told where to store the files that you edit. You would probably want to make some kind of folder for the project and make sure you store the text files in there.
I hope this helps! If you have any programmers nearby, they can probably get you started a lot faster than asking on StackOverflow.
I wanted to know what my options are for storing strings in a QT application.
One of my major requirements in not re-building the entire project or any file in-case one string changes and also have all the strings in one place.In short I would like to have the strings in one place and extract them during Application startup
I've used all of the elements talked about in above answers.
XML, JSON, QSettings w/ Ini files, tr()
All of them can do it just fine. I've put together some notes on the different options:
QTranslator
Qt Linguist and the tr() tags are designed to take your stock language and translate it into another language. Keeping track of multiple versions of the english translation and modifying/releasing without Qt Linguist is almost impossible. Qt Linguist is required to "release" your translations and convert them from a TS file (translation source) to an optimized QM file.
The QM file format is a compact binary format that is used by the localized application. It provides extremely fast lookups for translations.
Here is what using a translation file looks like:
QTranslator translator;
translator.load("hellotr_la");
app.installTranslator(&translator);
http://qt-project.org/doc/qt-4.8/qtranslator.html#details
I think using QTranslator for a few string changes may be a weird use case, unless you are using for localizing your program. But like the docs say, it is optimized for very fast look ups of string replacements.
QXMLStreamReader
The stream reader is "recommended" way to access XML files, or at least with better support. You write your own files for organizing it, or you write code to generate the XML.
<STRING_1>Some string</STRING_1>
Here is what it looks like to navigate into xml.
QXmlStreamReader xml;
...
while (!xml.atEnd()) {
xml.readNext();
... // do processing
}
if (xml.hasError()) {
... // do error handling
}
XML is very similar to Json, but with larger files and the start and end tags are longer. There are a lot more stock readers out there for XML. It is also a lot more human readable in many cases because so many people know html and they are very similar.
QJsonDocument
The JSON suppport in Qt 5 looks really good. I haven't built a project with it quite yet It is as easy as it looks, and as far as accessing and setting, it looks just like using a dictionary or a map or a vector.
UPDATE: You just pass around a pointer into your QJsonDocument or your QJsonObject or your QJsonArray as you are navigating deeper or appending more onto your Json file. And when you are done you can save it as a binary file, or as a clear text, human readable file, with proper indentation and everything!
How to create/read/write JSon files in Qt5
Json seems to be turning into the replacement for XML for many people. I like the example of using Json to save and load the state of a role playing game.
http://qt-project.org/doc/qt-5/qtcore-savegame-example.html
QSettings
QSettings is one of my favorites, just because it has been supported for so long, and it is how most persistent settings should be saved and accessed.
When I use it, to take advantage of the defaults and fall back mechanisms, I put this in my main.cpp:
QCoreApplication::setOrganizationName("MySoft");
QCoreApplication::setOrganizationDomain("mysoft.com");
QCoreApplication::setApplicationName("Star Runner");
And because I sometimes find a need to edit these setting by hand in windows, I use the Ini format.
QSettings::setDefaultFormat(QSettings::IniFormat); // also in main.cpp
Then when I deploy my exe, and I want to have particular value loaded instead of the hardcoded defaults, the installer drops the main fallback into
C:/ProgramData/MySoft/Star Runner.ini
And when the program saves a change at runtime, it gets saved to:
C:/Users/<username>/AppData/Roaming/MySoft/Star Runner.ini
And then throughout my program if I need to get a setting or set a setting, it takes 3 lines of code or less.
// setting the value
QSettings s;
s.setValue("Strings/string_1", "new string");
// getting the value
QString str;
QSettings s;
str = s.value("Strings/string_1", "default string").toString();
And here is what your ini file would look like:
[Strings]
string_1=default string
QSettings is the way to go if you are storing a few strings you want to change on deployment or at runtime. (or if a checkbox is now checked, or your window size and position, or the recent files list or whatever).
QSettings has been optimized quite a bit and is well thought out. The ini support is awesome, with the exception that it sometimes reorders groups and keys (usually alphabetically), and it may drop any comments you put in it. I think ini comments are either started with a ; or a #.
Hope that helps.
One way to do this would be to put it in a shared library. This way you can only recompile the shared library, but not the whole project. Another approach would be to put it in a file or a database and load it at runtime.
And of course you have to check your include dependencies. If you are including the headers everywhere, the compiler will rebuild everything that depends on it, even if the header is not really needed.
Another possible solution is to replace all strings with default ones inside tr() calls and use Qt Linguist to manage all the strings.
You'll also be able to load all the "translations" from external .qm file on startup.
It is simple: Store your volatile strings in QSettings http://qt-project.org/doc/qt-4.8/qsettings.html (you can use ini files or registry) or an XML file which will make you application configurable.
Edit: Well, after thinking about it a few more minutes, Guilherme's comment is right. QSettings will need to be initialized somehow (either manually or from some default values in your code)... and to be honest manual editing registry to change a few strings is not the brightest idea. So I conclude that XML or JSON is definitely better. It has advantages, for example you can keep several config files which allow you for switching languages at runtime etc.
I have seen instructions about creating a "skeleton" file in vim. This involves creating the file, naming it "tmpl" plus the extension of the file type you are targeting (ex: tmpl.html), saving it to the "skeleton" directory, and then editing the vimrc file.
But, in MacVim, I don't see a "skeleton" directory anywhere. Googling, etc., has returned no helpful information.
Can someone point me to a helpful tutorial/white paper/whatever to walk me through this process for MacVim?
I am determined to develop some skills with Vim/MacVim!
Thanks
I feel dirty giving this as an answer (because I've never done it), but googlin' gave me this: Vim Recipes: Using Templates.
Seems like you make your own skeleton directory and point the line for your .vimrc file to it.
There are a multitude of vim plugins that can handle this task. I use snipMate to perform tasks like this. You can define snippets for each file type or globally. The best part about the snippets is that you can keep hitting tab while it takes you to each "variable" within the snippet so that you can fill in the missing information quickly.
I have many source/text file, say file.cpp or file.txt . Now, I want to see all my code/text in browser, so that it will be easy for me to navigate many files.
My main motive for doing all this is, I am learning C++ myself, so whenever I learn something new, I create some sample code and then compile and run it. Also, along these codes, there are comments/tips for me to be aware of. And then I create links for each file for easy navigation purpose. Since, there are many such files, I thought it would be easy to navigate it if I use this html method. I am not sure if it is OK or good approach, I would like to have some feedback.
What I did was save file.cpp/file.txt into file.html and then use pre and code html tag for formatting. And, also some more necessare html tags for viewing html files.
But when I use it, everything inside < > is lost
eg. #include <iostream> is just seen as #include, and <iostream> is lost.
Is there any way to see it, is there any tag or method that I can use ?
I can use regular HTML escape code < and > for this, to see < > but since I have many include files and changing it for all of them is bit time-consuming, so I want to know if there is any other idea ??
So is there any other solution than s/</< and s/>/>
I would also like to know if there any other ideas/tips than just converting cpp file into html.
What I want to have is,
in my main page something like this,
tip1 Do this
tip2 Do that
When I click tip1, it will open tip1.html which has my codes for that tip. And also there is back link in tip1.html, which will take me back to main page on clicking it. Everything is OK just that everything inside < > is lost,not seen.
Thanks.
You might want to take a look at online tools such as CodeHtmler, which allows you to copy into the browser, select the appropriate language, and it'll convert to HTML for you, together with keyword colourisation etc.
Or, do like many other people and put your documentation in Doxygen format (/** */) with code samples in #verbatim/#endverbatim tags. Doxygen is good stuff.
A few ideas:
If you serve the files as mimetype text/plain, the browser should display the text for you.
You could also possibly configure your browser to assume .cpp is text/plain.
Instead of opening the files directly in the browser, you could serve them with a web server than can change the characters for you.
You could also use SyntaxHighlighter to display the code on the client side using JavaScript.
It is pretty much essential that somewhere along the line you use a program to prevent the characters '<>&' from being (mis-)interpreted by your browser (and expand significant repeated blanks into '` '). You have a couple of options for when/how to do that. You could use static HTML, simply converting each file once before putting it into the web server document hierarchy. This has the least conversion overhead if the files are looked at more often than they are modified. Alternatively, you can configure your web server to server the pages via a filter program (CGI, or something more sophisticated) and serve the output of that in lieu of the file. The advantage is that files are only converted when needed; the disadvantage is that the files are converted each time they are needed. You could get fancy and consider a caching solution - convert the file on first demand but retain the converted file for future use. The main downside there is that the web server needs to be able to write to where the converted file is cached - not necessarily a good idea for security reasons. (A minimalist approach to security requires the document hierarchy to be owned by and only writable by one user, say webmaster, and the web server runs as another user, say webserver. Now the web server cannot do any damage because it cannot write anywhere in the document hierarchy. Simple; effective; restrictive.)
The program can be a simple Perl script or a simple C program (the C source for webcode 1.3 is available here).
My Qt application should be able to create/open/save a single "Project" at once. What is the painless way to store project's settings in a file? Should it be XML or something less horrible?
Of course data to be stored in a file is a subject to change over time.
What I need is something like QSettings but bounded to a project in my application rather than to the whole application.
You can use QSettings to store data in a specific .ini file.
From the docs:
Sometimes you do want to access settings stored in a specific file or registry path. On all platforms, if you want to read an INI file directly, you can use the QSettings constructor that takes a file name as first argument and pass QSettings::IniFormat as second argument. For example:
QSettings settings("/home/petra/misc/myapp.ini",
QSettings::IniFormat);
I order to make it user editable, I would stick to plain text with one key = values by line, like in most of the Linux apps.
However this is only for the settings, not for the complete project's data which I suppose requires more complex structures.
So maybe JSON ?
Pro XML:
You can have a look at it in an editor
You can store any kind of string in any language in it (unicode support)
It's simple to learn
More than one program can read the same XML
It's easy to structure your data with XML. When you use key/value lists, for example, you'll run into problems when you need to save tree-like structures.
Contra XML
The result is somewhat bloated
Most programming languages (especially old ones like C++) have no good support for XML. The old XML APIs were designed in such a way that they could be implemented in any language (smallest common denominator). 'nuff said.
You need to understand the concept of "encoding" (or "charset"). While this may look trivial at first glance, there are some hidden issues which can bite you. So always test your code with some umlauts and even kanji (Japanese characters) to make sure you got it right.