Search Results

Search found 464 results on 19 pages for 'grammar nazi'.

Page 16/19 | < Previous Page | 12 13 14 15 16 17 18 19  | Next Page >

• on coding style

  - by user12607414

  I vastly prefer coding to discussing coding style, just as I would prefer to write poetry instead of talking about how it should be written. Sometimes the topic cannot be put off, either because some individual coder is messing up a shared code base and needs to be corrected, or (worse) because some officious soul has decided, "what we really need around here are some strongly enforced style rules!" Neither is the case at the moment, and yet I will venture a post on the subject. The following are not rules, but suggested etiquette. The idea is to allow a coherent style of coding to flourish safely and sanely, as a humane, inductive, social process. Maxim M1: Observe, respect, and imitate the largest-scale precedents available. (Preserve styles of whitespace, capitalization, punctuation, abbreviation, name choice, code block size, factorization, type of comments, class organization, file naming, etc., etc., etc.) Maxim M2: Don't add weight to small-scale variations. (Realize that Maxim M1 has been broken many times, but don't take that as license to create further irregularities.) Maxim M3: Listen to and rely on your reviewers to help you perceive your own coding quirks. (When you review, help the coder do this.) Maxim M4: When you touch some code, try to leave it more readable than you found it. (When you review such changes, thank the coder for the cleanup. When you plan changes, plan for cleanups.) On the Hotspot project, which is almost 1.5 decades old, we have often practiced and benefited from such etiquette. The process is, and should be, inductive, not prescriptive. An ounce of neighborliness is better than a pound of police-work. Reality check: If you actually look at (or live in) the Hotspot code base, you will find we have accumulated many annoying irregularities in our source base. I suppose this is the normal condition of a lived-in space. Unless you want to spend all your time polishing and tidying, you can't live without some smudge and clutter, can you? Final digression: Grammars and dictionaries and other prescriptive rule books are sometimes useful, but we humans learn and maintain our language by example not grammar. The same applies to style rules. Actually, I think the process of maintaining a clean and pleasant working code base is an instance of a community maintaining its common linguistic identity. BTW, I've been reading and listening to John McWhorter lately with great pleasure. (If you end with a digression, is it a tail-digression?)

  Read the article

• Data validation best practices: how can I better construct user feedback?

  - by Cory Larson

  Data validation, whether it be domain object, form, or any other type of input validation, could theoretically be part of any development effort, no matter its size or complexity. I sometimes find myself writing informational or error messages that might seem harsh or demanding to unsuspecting users, and frankly I feel like there must be a better way to describe the validation problem to the user. I know that this topic is subjective and argumentative. StackOverflow might not be the proper channel for diving into this subject, but like I've mentioned, we all run into this at some point or another. There are so many StackExchange sites now; if there is a better one, feel free to share! Basically, I'm looking for good resources on data validation and user feedback that results from it at a theoretical level. Topics and questions I'm interested in are: Content Should I be describing what the user did correctly or incorrectly, or simply what was expected? How much detail can the user read before they get annoyed? (e.g. Is "Username cannot exceed 20 characters." enough, or should it be described more fully, such as "The username cannot be empty, and must be at least 6 characters but cannot exceed 30 characters."?) Grammar How do I decide between phrases like "must not," "may not," or "cannot"? Delivery This can depend on the project, but how should the information be delivered to the user? Should it be obtrusive (e.g. JavaScript alerts) or friendly? Should they be displayed prominently? Immediately (i.e. without confirmation steps, etc.)? Logging Do you bother logging validation errors? Internationalization Some cultures prefer or better understand directness over subtlety and vice-versa (e.g. "Don't do that!" vs. "Please check what you've done."). How do I cater to the majority of users? I may edit this list as I think more about the topic, but I'm genuinely interest in proper user feedback techniques. I'm looking for things like research results, poll results, etc. I've developed and refined my own techniques over the years that users seem to be okay with, but I work in an environment where the users prefer to adapt to what you give them over speaking up about things they don't like. I'm interested in hearing your experiences in addition to any resources to which you may be able to point me.

  Read the article

• What are the arguments against parsing the Cthulhu way?

  - by smarmy53

  I have been assigned the task of implementing a Domain Specific Language for a tool that may become quite important for the company. The language is simple but not trivial, it already allows nested loops, string concatenation, etc. and it is practically sure that other constructs will be added as the project advances. I know by experience that writing a lexer/parser by hand -unless the grammar is trivial- is a time consuming and error prone process. So I was left with two options: a parser generator à la yacc or a combinator library like Parsec. The former was good as well but I picked the latter for various reasons, and implemented the solution in a functional language. The result is pretty spectacular to my eyes, the code is very concise, elegant and readable/fluent. I concede it may look a bit weird if you never programmed in anything other than java/c#, but then this would be true of anything not written in java/c#. At some point however, I've been literally attacked by a co-worker. After a quick glance at my screen he declared that the code is uncomprehensible and that I should not reinvent parsing but just use a stack and String.Split like everybody does. He made a lot of noise, and I could not convince him, partially because I've been taken by surprise and had no clear explanation, partially because his opinion was immutable (no pun intended). I even offered to explain him the language, but to no avail. I'm positive the discussion is going to re-surface in front of management, so I'm preparing some solid arguments. These are the first few reasons that come to my mind to avoid a String.Split-based solution: you need lot of ifs to handle special cases and things quickly spiral out of control lots of hardcoded array indexes makes maintenance painful extremely difficult to handle things like a function call as a method argument (ex. add( (add a, b), c) very difficult to provide meaningful error messages in case of syntax errors (very likely to happen) I'm all for simplicity, clarity and avoiding unnecessary smart-cryptic stuff, but I also believe it's a mistake to dumb down every part of the codebase so that even a burger flipper can understand it. It's the same argument I hear for not using interfaces, not adopting separation of concerns, copying-pasting code around, etc. A minimum of technical competence and willingness to learn is required to work on a software project after all. (I won't use this argument as it will probably sound offensive, and starting a war is not going to help anybody) What are your favorite arguments against parsing the Cthulhu way?* *of course if you can convince me he's right I'll be perfectly happy as well

  Read the article

• CMS vs Admin Panel?

  - by Bob

  Okay, so this probably seems like an unusual, more grammar related question, but I was unsure of what to call it. If you use a software such as vBulletin or MyBB or even Blogger and you're the administrator (or other, lesser position such as moderator) of the forum, or publisher/author of the blog, you generally have access to something of an "admin panel". For example, vBulletin's admin panel looks like this and Blogger's admin panel looks something like this. While they both look different and do different things, the goal is fundamentally the same: to provide the user with a method for adding, modifying, or deleting content... to let them control and administrate their forum or blog. Also, they're both made specifically by the company for use in a specific product. Now, there's also options like Drupal. It seems to offer quite a bit more and be quite a bit more generalized. How does something like this work? If you were freelancing, would you deploy a website with Drupal, or would it be something the client might already have installed on their own server? I've never really used Drupal, only heard about it, so please let me know. Also, there seems to be other options like cPanel, a sort of global CMS that allows you to administrate over your entire website. How do those work in comparison to Drupal, or the administrative panels with vBulletin? They seem to serve related, but different purposes. Basically, what is the norm? If I'm developing a web application for a group that needs to be able to edit their website without the need to go into the code or the database (or rather, wants to act in a graphical, easy-to-use content-management/admin panel), would it also be necessary to write my own miniature admin panel? Or would I be able to send them off knowing that they have cPanel? Or could something like Drupal fill this void? Again, I'm a little new to web development, and I'm working on planning out my first, real, large website. So I need a little advice on the standards and expectations for web development - security and coding practices aside, what should I be looking for as far as usability and administration for the client (who will be running the site once I'm done creating the website)? Any extra tips would also be appreciated! Oh, and just a little bit: I'm writing the website using Ruby on the Sinatra framework (both Ruby and Sinatra are things I'm fairly comfortable with) and I'm not being paid to make the website (and I will also be a user, and one of the three administrators of the website) - it's being built for a club I'm in.

  Read the article

• Need help fixing DPKG errors after update from 12.04 to 12.10

  - by James Wulfe

  So I was doing fine then i upgraded my system to 12.10 and now i cant get my system to update all of its packages properly. no matter what i do, what is happening here and how do i fix this. if i would have thought 12.10 would be this much of a hassle i would have never upgraded..... here is a sampling of the code that returns from "apt-get -f install" It should also be noted that it is just these 6 packages only. no other packages have given me this kind of trouble. well i should say as of now. It was just 5, but them i got an update for unity, and now unity-common is added to the trouble makers. which prevents me from further upgrading the actual unity package as this package is a dependancy. Preparing to replace usb-modeswitch-data 20120120-0ubuntu1 (using .../usb-modeswitch-data_20120815-1_all.deb) ... /var/lib/dpkg/info/usb-modeswitch-data.prerm: 4: /var/lib/dpkg/info/usb-modeswitch-data.prerm: dpkg-maintscript-helper: Input/output error dpkg: warning: subprocess old pre-removal script returned error exit status 2 dpkg: trying script from the new package instead ... /var/lib/dpkg/tmp.ci/prerm: 4: /var/lib/dpkg/tmp.ci/prerm: dpkg-maintscript-helper: Input/output error dpkg: error processing /var/cache/apt/archives/usb-modeswitch-data_20120815-1_all.deb (--unpack): subprocess new pre-removal script returned error exit status 2 /var/lib/dpkg/info/usb-modeswitch-data.postinst: 7: /var/lib/dpkg/info/usb-modeswitch-data.postinst: dpkg-maintscript-helper: Input/output error dpkg: error while cleaning up: subprocess installed post-installation script returned error exit status 2 Errors were encountered while processing: /var/cache/apt/archives/network-manager_0.9.6.0-0ubuntu7_i386.deb /var/cache/apt/archives/pcmciautils_018-8_i386.deb /var/cache/apt/archives/unity-common_6.10.0-0ubuntu2_all.deb /var/cache/apt/archives/whoopsie_0.2.7_i386.deb /var/cache/apt/archives/usb-modeswitch_1.2.3+repack0-1ubuntu3_i386.deb /var/cache/apt/archives/usb-modeswitch-data_20120815-1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1) I would also like to note i have cleaned apt cashe both through the terminal and manualy, i have tried installing them manually through dpkg from both the /var/cache/apt/archives/ location and from my own manually downloaded .deb files. i have tried using dpkg-reconfigure and i have used bleachbit to clean my system. I have also tested both my HDD and memory and found no significant errors to lead to the input/output errors. Quite frankly i am just out of options and have grown tired of trying to google a solution to this mess but still do not wish to pursue backing up settings and reinstalling the system. Any help would be appreciated. I am only interested in answers, please leave your feeling towards grammar, punctuation, and bias towards how a "post should look" at the door. If you dont have something to contribute towards solving my problem then you are just doing nothing but contributing to it. Thank you.

  Read the article

• Collision in PyGame for spinning rectangular object.touching circles

  - by OverAchiever

  I'm creating a variation of Pong. One of the differences is that I use a rectangular structure as the object which is being bounced around, and I use circles as paddles. So far, all the collision handling I've worked with was using simple math (I wasn't using the collision "feature" in PyGame). The game is contained within a 2-dimensional continuous space. The idea is that the rectangular structure will spin at different speed depending on how far from the center you touch it with the circle. Also, any extremity of the rectangular structure should be able to touch any extremity of the circle. So I need to keep track of where it has been touched on both the circle and the rectangle to figure out the direction it will be bounced to. I intend to have basically 8 possible directions (Up, down, left, right and the half points between each one of those). I can work out the calculation of how the objected will be dislocated once I get the direction it will be dislocated to based on where it has been touch. I also need to keep track of where it has been touched to decide if the rectangular structure will spin clockwise or counter-clockwise after it collided. Before I started coding, I read the resources available at the PyGame website on the collision class they have (And its respective functions). I tried to work out the logic of what I was trying to achieve based on those resources and how the game will function. The only thing I could figure out that I could do was to make each one of these objects as a group of rectangular objects, and depending on which rectangle was touched the other would behave accordingly and give the illusion it is a single object. However, not only I don't know if this will work, but I also don't know if it is gonna look convincing based on how PyGame redraws the objects. Is there a way I can use PyGame to handle these collision detections by still having a single object? Can I figure out the point of collision on both objects using functions within PyGame precisely enough to achieve what I'm looking for? P.s: I hope the question was specific and clear enough. I apologize if there were any grammar mistakes, English is not my native language.

  Read the article

• How to get lookahead symbol when constructing LR(1) NFA for parser?

  - by greenoldman

  I am reading an explanation (awesome "Parsing Techniques" by D.Grune and C.J.H.Jacobs; p.292 in the 2nd edition) about how to construct an LR(1) parser, and I am at the stage of building the initial NFA. What I don't understand is how to get/compute a lookahead symbol. Here is the example from the book, the grammar: S -> E E -> E - T E -> T T -> ( E ) T -> n n is terminal. The "weird" transitions for me are is the sequence: 1) S -> . E eof 2) E -> . E - T eof 3) E -> . E - T - 4) E -> E . - T - 5) E -> E - . T - (Note: In the above table, the state numbers are in front and the lookahead symbol is at the end.) What puzzles me is that transition from (4) to (5) means reading - token, right? So how is it that - is still a lookahead symbol and even more important why is it that eof is no longer a lookahead symbol? After all in an input such as n - n eof there is only one - symbol. My naive thinking tells me (5) should be written as: 5) E -> E - . T - eof And another thing -- n is terminal. Why it is not used at all as a lookahead symbol? I mean -- we expect to see - or (, it is ok, but lack of n means we are sure it won't appear in input? Update: after more reading I am only more confused ;-) I.e. what is really a lookahead? Because I see such state as (p.292, 2nd column, 2nd row): E -> E . - T eof Lookahead says eof but the incoming input says -. Isn't it a contradiction? And it is not only in this book.

  Read the article

• Cannot Add Particular Word to Dictionary

  - by WCWedin

  I am trying to add a particular word to my custom dictionary using Word 2007. (The word happens to be "deserialized".) When I right-click on the word and click Add to Dictionary, the red underline does not go away. When I use the Spelling & Grammar tool from the Review tab on the ribbon, it will stop on that word; clicking the Add to Dictionary button has no effect. Oddly, I am able to add other words to the custom dictionary without a problem. I recently added "deserializes", for instance. I have only encountered this problem with that one particular word. Does anyone know what might be wrong and how I might fix it? Clarifications My document and all its content is set to English (United States). My custom dictionary is set to apply to All Languages, which is the default value. "Serialize" is in the US English default dictionary, but "deserialize" and its various forms is not.

  Read the article

• Hibernate Exception, what wrong ? [[Exception in thread "main" org.hibernate.InvalidMappingException

  - by user195970

  I use netbean 6.7.1 to write "hello world" witch hibernate, but I get some errors, plz help me, thank you very much. my exception init: deps-module-jar: deps-ear-jar: deps-jar: Copying 1 file to F:\Documents and Settings\My Dropbox\DropboxNetBeanProjects\loginspring\build\web\WEB-INF\classes compile-single: run-main: Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Environment <clinit> INFO: Hibernate 3.2.5 Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Environment <clinit> INFO: hibernate.properties not found Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Environment buildBytecodeProvider INFO: Bytecode provider name : cglib Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Environment <clinit> INFO: using JDK 1.4 java.sql.Timestamp handling Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Configuration configure INFO: configuring from resource: /hibernate.cfg.xml Oct 25, 2009 2:44:05 AM org.hibernate.cfg.Configuration getConfigurationInputStream INFO: Configuration resource: /hibernate.cfg.xml Oct 25, 2009 2:44:06 AM org.hibernate.cfg.Configuration addResource INFO: Reading mappings from resource : hibernate/Tbluser.hbm.xml Oct 25, 2009 2:44:06 AM org.hibernate.util.XMLHelper$ErrorLogger error SEVERE: Error parsing XML: XML InputStream(1) Document is invalid: no grammar found. Oct 25, 2009 2:44:06 AM org.hibernate.util.XMLHelper$ErrorLogger error SEVERE: Error parsing XML: XML InputStream(1) Document root element "hibernate-mapping", must match DOCTYPE root "null". Exception in thread "main" org.hibernate.InvalidMappingException: Could not parse mapping document from resource hibernate/Tbluser.hbm.xml at org.hibernate.cfg.Configuration.addResource(Configuration.java:569) at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:1587) at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:1555) at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1534) at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1508) at org.hibernate.cfg.Configuration.configure(Configuration.java:1428) at org.hibernate.cfg.Configuration.configure(Configuration.java:1414) at hibernate.CreateTest.main(CreateTest.java:22) Caused by: org.hibernate.InvalidMappingException: Could not parse mapping document from invalid mapping at org.hibernate.cfg.Configuration.addInputStream(Configuration.java:502) at org.hibernate.cfg.Configuration.addResource(Configuration.java:566) ... 7 more Caused by: org.xml.sax.SAXParseException: Document is invalid: no grammar found. at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:195) at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:131) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:384) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:318) at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:250) at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl$NSContentDriver.scanRootElementHook(XMLNSDocumentScannerImpl.java:626) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:3095) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:921) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648) at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:140) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:807) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737) at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:107) at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205) at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522) at org.dom4j.io.SAXReader.read(SAXReader.java:465) at org.hibernate.cfg.Configuration.addInputStream(Configuration.java:499) ... 8 more Java Result: 1 BUILD SUCCESSFUL (total time: 1 second) hibernate.cfg.xml <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate</property> <property name="hibernate.connection.username">root</property> </session-factory> </hibernate-configuration> Tbluser.hbm.xml <?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <!-- Generated Oct 25, 2009 2:37:30 AM by Hibernate Tools 3.2.1.GA --> <hibernate-mapping> <class name="hibernate.Tbluser" table="tbluser" catalog="hibernate"> <id name="userId" type="java.lang.Integer"> <column name="userID" /> <generator class="identity" /> </id> <property name="username" type="string"> <column name="username" length="50" /> </property> <property name="password" type="string"> <column name="password" length="50" /> </property> <property name="email" type="string"> <column name="email" length="50" /> </property> <property name="phone" type="string"> <column name="phone" length="50" /> </property> <property name="groupId" type="java.lang.Integer"> <column name="groupID" /> </property> </class> </hibernate-mapping> Tbluser.java package hibernate; // Generated Oct 25, 2009 2:37:30 AM by Hibernate Tools 3.2.1.GA /** * Tbluser generated by hbm2java */ public class Tbluser implements java.io.Serializable { private Integer userId; private String username; private String password; private String email; private String phone; private Integer groupId; public Tbluser() { } public Tbluser(String username, String password, String email, String phone, Integer groupId) { this.username = username; this.password = password; this.email = email; this.phone = phone; this.groupId = groupId; } public Integer getUserId() { return this.userId; } public void setUserId(Integer userId) { this.userId = userId; } public String getUsername() { return this.username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return this.password; } public void setPassword(String password) { this.password = password; } public String getEmail() { return this.email; } public void setEmail(String email) { this.email = email; } public String getPhone() { return this.phone; } public void setPhone(String phone) { this.phone = phone; } public Integer getGroupId() { return this.groupId; } public void setGroupId(Integer groupId) { this.groupId = groupId; } }

  Read the article

• Need help regarding one LALR(1) parsing.

  - by AppleGrew

  I am trying to parse a context-free language, called Context Free Art. I have created its parser in Javascript using a YACC-like JS LALR(1) parser generator JSCC. Take the example of following CFA (Context Free Art) code. This code is a valid CFA. startshape A rule A { CIRCLE { s 1} } Notice the A and s in above. s is a command to scale the CIRCLE, but A is just a name of this rule. In the language's grammar I have set s as token SCALE and A comes under token STRING (I have a regular expression to match string and it is at the bottom of of all tokens). This works fine, but in the below case it breaks. startshape s rule s { CIRCLE { s 1} } This too is a perfectly valid code, but since my parser marks s after rule as SCALE token so it errors out saying that it was expecting STRING. Now my question is, if there is any way to re-write the production rules of the parser to account for this? The related production rule is:- rule: RULE STRING '{' buncha_replacements '}' [* rule(%2, 1) *] | RULE STRING RATIONAL '{' buncha_replacements '}' [* rule(%2, 1*%3) *] ; One simple solution I can think of is create a copy of above rule with STRING replaced by SCALE, but this is just one of the many similar rules which would need such fixing. Furthermore there are many other terminals which can get matched to STRING. So that means way too many rules!

  Read the article

• Parsing an arithmetic expression and building a tree from it in Java

  - by ChocolateBear

  Hi, I needed some help with creating custom trees given an arithmetic expression. Say, for example, you input this arithmetic expression: (5+2)*7 The result tree should look like: * / \ + 7 / \ 5 2 I have some custom classes to represent the different types of nodes, i.e. PlusOp, LeafInt, etc. I don't need to evaluate the expression, just create the tree, so I can perform other functions on it later. Additionally, the negative operator '-' can only have one child, and to represent '5-2', you must input it as 5 + (-2). Some validation on the expression would be required to ensure each type of operator has the correct the no. of arguments/children, each opening bracket is accompanied by a closing bracket. Also, I should probably mention my friend has already written code which converts the input string into a stack of tokens, if that's going to be helpful for this. I'd appreciate any help at all. Thanks :) (I read that you can write a grammar and use antlr/JavaCC, etc. to create the parse tree, but I'm not familiar with these tools or with writing grammars, so if that's your solution, I'd be grateful if you could provide some helpful tutorials/links for them.)

  Read the article

• Big problem with regular expression in Lex (lexical analyzer)

  - by Nazgulled

  Hi, I have some content like this: author = "Marjan Mernik and Viljem Zumer", title = "Implementation of multiple attribute grammar inheritance in the tool LISA", year = 1999 author = "Manfred Broy and Martin Wirsing", title = "Generalized Heterogeneous Algebras and Partial Interpretations", year = 1983 author = "Ikuo Nakata and Masataka Sassa", title = "L-Attributed LL(1)-Grammars are LR-Attributed", journal = "Information Processing Letters" And I need to catch everything between double quotes for title. My first try was this: ^(" "|\t)+"title"" "*=" "*"\"".+"\"," Which catches the first example, but not the other two. The other have multiple lines and that's the problem. I though about changing to something with \n somewhere to allow multiple lines, like this: ^(" "|\t)+"title"" "*=" "*"\""(.|\n)+"\"," But this doesn't help, instead, it catches everything. Than I though, "what I want is between double quotes, what if I catch everything until I find another " followed by ,? This way I could know if I was at the end of the title or not, no matter the number of lines, like this: ^(" "|\t)+"title"" "*=" "*"\""[^"\""]+"," But this has another problem... The example above doesn't have it, but the double quote symbol (") can be in between the title declaration. For instance: title = "aaaaaaa \"X bbbbbb", And yes, it will always be preceded by a backslash (\). Any suggestions to fix this regexp?

  Read the article

• Parsing some particular statements with antlr3 in C target

  - by JCD

  Hello all! I have some questions about antlr3 with tree grammar in C target. I have almost done my interpretor (functions, variables, boolean and math expressions ok) and i have kept the most difficult statements for the end (like if, switch, etc.) 1) I would like interpreting a simple loop statement: repeat: ^(REPEAT DIGIT stmt); I've seen many examples but nothing about the tree walker (only a topic here with the macros MARK() / REWIND(m) + @init / @after but not working (i've antlr errors: "unexpected node at offset 0")). How can i interpret this statement in C? 2) Same question with a simple if statement: if: ^(IF condition stmt elseifstmt* elsestmt?); The problem is to skip the statement if the condition is false and test the other elseif/else statements. 3) I have some statements which can stop the script (like "break" or "exit"). How can i interrupt the tree walker and skip the following tokens? 4) When a lexer or parser error is detected, antlr returns an error. But i would like to make my homemade error messages. How can i have the line number where parser crashed? Ask me if you want more details. Thanks you very much (and i apologize for my poor english)

  Read the article

• Problem calling std::max

  - by Eric

  I compiled my bison-generated files in Visual Studio and got these errors: ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' The corresponding code is: inline void columns (int count = 1) { column = std::max (1u, column + count); } I think the problem is with std::max; if I change std::max to equivalent code then there is no problem anymore, but is there a better solution instead of changing the generated code? Here is the bison file I wrote: // // bison.yy // %skeleton "lalr1.cc" %require "2.4.2" %defines %define parser_class_name "cmd_parser" %locations %debug %error-verbose %code requires { class ParserDriver; } %parse-param { ParserDriver& driver } %lex-param { ParserDriver& driver } %union { struct ast *a; double d; struct symbol *s; struct symlist *sl; int fn; } %code { #include "helper_func.h" #include "ParserDriver.h" std::string error_msg = ""; } %token <d> NUMBER %token <s> NAME %token <fn> FUNC %token EOL %token IF THEN ELSE WHILE DO LET %token SYM_TABLE_OVERFLOW %token UNKNOWN_CHARACTER %nonassoc <fn> CMP %right '=' %left '+' '-' %left '*' '/' %nonassoc '|' UMINUS %type <a> exp stmt list explist %type <sl> symlist %{ extern int yylex(yy::cmd_parser::semantic_type *yylval, yy::cmd_parser::location_type* yylloc); %} %start calclist %% ... grammar rules ...

  Read the article

• Programming Technique: How to create a simple card game

  - by Shyam

  Hi, As I am learning the Ruby language, I am getting closer to actual programming. So I was thinking of creating a simple card game. My question isn't Ruby orientated, but I do know want to learn how to solve this problem with a genuine OOP approach. In my card game I want to have four players. Using a standard deck with 52 cards, no jokers/wildcards. In the game I won't use the Ace as a dual card, it is always the highest card. So, the programming problems I wonder about are the following: How can I sort/randomize the deck of cards? There are four types, each having 13 values. Eventually there can be only unique values, so picking random values could generate duplicates. How can I implement a simple AI? As there are tons of card games, someone would have figured this part out already, so references would be great. I am a truly Ruby nuby, and my goal here is to learn to solve problems, so pseudo code would be great, just to understand how to solve the problem programmatically. I apologize for my grammar and writing style if it's unclear, for it is not my native language. Also pointers to sites where such challenges are explained, would be a great resource! Thank you for your comments, answers and feedback!

  Read the article

• executing stored procedure from Spring-Hibernate using Annotations

  - by HanuAthena

  I'm trying to execute a simple stored procedure with Spring/Hibernate using Annotations. Here are my code snippets: DAO class: public class UserDAO extends HibernateDaoSupport { public List selectUsers(final String eid){ return (List) getHibernateTemplate().execute(new HibernateCallback() { public Object doInHibernate(Session session) throws HibernateException, SQLException { Query q = session.getNamedQuery("SP_APPL_USER"); System.out.println(q); q.setString("eid", eid); return q.list(); } }); } } my entity class: @Entity @Table(name = "APPL_USER") @Inheritance(strategy = InheritanceType.SINGLE_TABLE) @DiscriminatorFormula(value = "SUBSCRIBER_IND") @DiscriminatorValue("N") @NamedQuery(name = "req.all", query = "select n from Requestor n") @org.hibernate.annotations.NamedNativeQuery(name = "SP_APPL_USER", query = "call SP_APPL_USER(?, :eid)", callable = true, readOnly = true, resultClass = Requestor.class) public class Requestor { @Id @Column(name = "EMPL_ID") public String getEmpid() { return empid; } public void setEmpid(String empid) { this.empid = empid; } @Column(name = "EMPL_FRST_NM") public String getFirstname() { return firstname; } ... } public class Test { public static void main(String[] args) { ApplicationContext ctx = new ClassPathXmlApplicationContext( "applicationContext.xml"); APFUser user = (APFUser)ctx.getBean("apfUser"); List selectUsers = user.getUserDAO().selectUsers("EMP456"); System.out.println(selectUsers); } } and the stored procedure: create or replace PROCEDURE SP_APPL_USER (p_cursor out sys_refcursor, eid in varchar2) as empId varchar2(8); fname varchar2(50); lname varchar2(50); begin empId := null; fname := null; lname := null; open p_cursor for select l.EMPL_ID, l.EMPL_FRST_NM, l.EMPL_LST_NM into empId, fname, lname from APPL_USER l where l.EMPL_ID = eid; end; If i enter invalid EID, its returning empty list which is OK. But when record is there, following exception is thrown: Exception in thread "main" org.springframework.jdbc.BadSqlGrammarException: Hibernate operation: could not execute query; bad SQL grammar [call SP_APPL_USER(?, ?)]; nested exception is java.sql.SQLException: Invalid column name Do I need to modify the entity(Requestor.class) ? How will the REFCURSOR be converted to the List? The stored procedure is expected to return more than one record.

  Read the article

• errors when using c++ bison ---- in the file position.hh

  - by Eric

  firstly I'm not good at English so forgive me. I compile my program with the bison generated files in visual studio and get these errors: ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' and the corresponding code is: inline void columns (int count = 1) { column = std::max (1u, column + count); } I think the problem is with std::max. If I change std::max to equivalent code then there is problem anymore, but is there a better solution instead of changing the generated code? here is the *.yy file I wrote. // // bison.yy // %skeleton "lalr1.cc" %require "2.4.2" %defines %define parser_class_name "cmd_parser" %locations %debug %error-verbose %code requires { class ParserDriver; } %parse-param { ParserDriver& driver } %lex-param { ParserDriver& driver } %union { struct ast *a; double d; struct symbol *s; struct symlist *sl; int fn; } %code { #include "helper_func.h" #include "ParserDriver.h" std::string error_msg = ""; } %token <d> NUMBER %token <s> NAME %token <fn> FUNC %token EOL %token IF THEN ELSE WHILE DO LET %token SYM_TABLE_OVERFLOW %token UNKNOWN_CHARACTER %nonassoc <fn> CMP %right '=' %left '+' '-' %left '*' '/' %nonassoc '|' UMINUS %type <a> exp stmt list explist %type <sl> symlist %{ extern int yylex(yy::cmd_parser::semantic_type *yylval, yy::cmd_parser::location_type* yylloc); %} %start calclist %% ... grammar rules ...

  Read the article

• Can Haskell's Parsec library be used to implement a recursive descent parser with backup?

  - by Thor Thurn

  I've been considering using Haskell's Parsec parsing library to parse a subset of Java as a recursive descent parser as an alternative to more traditional parser-generator solutions like Happy. Parsec seems very easy to use, and parse speed is definitely not a factor for me. I'm wondering, though, if it's possible to implement "backup" with Parsec, a technique which finds the correct production to use by trying each one in turn. For a simple example, consider the very start of the JLS Java grammar: Literal: IntegerLiteral FloatingPointLiteral I'd like a way to not have to figure out how I should order these two rules to get the parse to succeed. As it stands, a naive implementation like this: literal = do { x <- try (do { v <- integer; return (IntLiteral v)}) <|> (do { v <- float; return (FPLiteral v)}); return(Literal x) } Will not work... inputs like "15.2" will cause the integer parser to succeed first, and then the whole thing will choke on the "." symbol. In this case, of course, it's obvious that you can solve the problem by re-ordering the two productions. In the general case, though, finding things like this is going to be a nightmare, and it's very likely that I'll miss some cases. Ideally, I'd like a way to have Parsec figure out stuff like this for me. Is this possible, or am I simply trying to do too much with the library? The Parsec documentation claims that it can "parse context-sensitive, infinite look-ahead grammars", so it seems like something like I should be able to do something here.

  Read the article

• Writing language converter in ANTLR

  - by Stefan

  I'm writing a converter between some dialects of the same programming language. I've found a grammar on the net - it's complex and handles all the cases. Now I'm trying to write the appropriate actions. Most of the input is just going to be rewritten to output. What I need to do is parse function calls, do my magic (rename function, reorder arguments, etc) and write it. I'm using AST as output. When I come across a function call, I build a custom object structure (from classes defined in my target language), call the appropriate function and I have a string that represents the transformed function that I want to get. The problem is, what I'm supposed to do with that string? I'd like to replace the .text attribute of the enclosing rule, but setText() is only available on lexer rules and the rule's .text attribute is read-only. How to solve this problem? program : statement_list { output = $statement_list.text; } ; //... statement : expression_statement // ... ; expression_statement : function_call // ... ; function_call : ID '(' { /* build the object, assign name */ Function function = new Function(); //... } ( arg1 = expression { /* add first parameter */ } ( ',' arg2 = expression { /* add the rest of parameters */ } )* )? ')' { /* convert the function call */ string converted = Tools.Convert(function); // $setText(converted); // doesn't work // $functionCall.text = converted; // doesn't work } ;

  Read the article

• Why linking doesn't work in my Xtext-based DSL?

  - by reprogrammer

  The following is the Xtext grammar for my DSL. Model: variableTypes=VariableTypes predicateTypes=PredicateTypes variableDeclarations= VariableDeclarations rules=Rules; VariableType: name=ID; VariableTypes: 'var types' (variableTypes+=VariableType)+; PredicateTypes: 'predicate types' (predicateTypes+=PredicateType)+; PredicateType: name=ID '(' (variableTypes+=[VariableType|ID])+ ')'; VariableDeclarations: 'vars' (variableDeclarations+=VariableDeclaration)+; VariableDeclaration: name=ID ':' type=[VariableType|ID]; Rules: 'rules' (rules+=Rule)+; Rule: head=Head ':-' body=Body; Head: predicate=Predicate; Body: (predicates+=Predicate)+; Predicate: predicateType=[PredicateType|ID] '(' (terms+=Term)+ ')'; Term: variable=Variable; Variable: variableDeclaration=[VariableDeclaration|ID]; terminal WS: (' ' | '\t' | '\r' | '\n' | ',')+; And, the following is a program in the above DSL. var types Node predicate types Edge(Node, Node) Path(Node, Node) vars x : Node y : Node z : Node rules Path(x, y) :- Edge(x, y) Path(x, y) :- Path(x, z) Path(z, y) When I used the generated Switch class to traverse the EMF object model corresponding to the above program, I realized that the nodes are not linked together properly. For example, the getPredicateType() method on a Predicate node returns null. Having read the Xtext user's guide, my impression is that the Xtext default linking semantics should work for my DSL. But, for some reason, the AST nodes of my DSL don't get linked together properly. Can anyone help me in diagnosing this problem?

  Read the article

• How to set UCS2 in numpy?

  - by mindcorrosive

  I'm trying to build numpy 1.2.1 as a module for a third-party python interpreter (custom-built, py2.4 linux x86_64) so that I can make calls to numpy from within it. Let's call this one interpreter A. The thing is, the system-wide python interpreter (also py2.4, let's call it B) from the vendor is built with --enable-unicode=ucs4, while the custom one is with UCS2. Needless to say, when I try to build a module with B, I get an error when I try to import numpy in A -- it complains about undefined symbol _PyUnicodeUCS4_IsWhiteSpace. I've searched around and apparently there's no way around this but to compile a custom Python interpreter -- which I did (let's call it interpreter C), properly specifying the unicode string length (verifiable through sys.maxunicode). I managed to build numpy with C as well, surprisingly enough, but still the problem persists when I try to import it in interpreter C. Previously, when I built numpy using B, there were no problems when importing it in B, but A would complain. Perhaps there's an option when building numpy to specify the length of Unicode strings to be used, as when configuring Python builds? Or am I doing something else wrong? A few notes: Upgrading to newer versions of python and/or numpy is not an option - interpreter A will stay on this version of the grammar for the foreseeable future. Also, it is not possible to start the interpreter A in standalone mode to build numpy with it, as it needs some other libraries preloaded I know that this whole thing is a mess, but I'd appreciate any help I can get to make this work. If you need more information, please let me know, I'd be happy to oblige. Thanks to everybody for their time in advance.

  Read the article

• How would you go about parsing markdown?

  - by John Leidegren

  You can find the syntax here. The thing is, the source that follows with the download is written in perl. Which I have no intentions of honoring. It is riddled with regex and it relies on MD5 hashes to escape certain characters. Something is just wrong about that! I'm about to hard code a parser for markdown and I'm wonder if someone had some experience with this? Edit: If you don't have anything meaningful to say about the actual parsing of markdown, spare me the time. (This might sound harsh, but yes, I'm looking for insight, not a solution i.e. third-party library). To help a bit with the answers, regex are meant to identify patterns! NOT to parse an entire grammar. That people consider doing so is foobar. If you think about markdown, it's fundamentally based around the concept of paragraphs. As such, a reasonable approach might be to split the input into paragraphs. There are many kinds of paragraphs e.g. heading, text, list, blockquote, code. The challenge is thus to identify these paragraphs and in what context they occur. I'll be back with a solution, once I find it's worthy to be shared.

  Read the article

• How do I get Bison/YACC to not recognize a command until it parses the whole string?

  - by chucknelson

  I have some bison grammar: input: /* empty */ | input command ; command: builtin | external ; builtin: CD { printf("Changing to home directory...\n"); } | CD WORD printf("Changing to directroy %s\n", $2); } ; I'm wondering how I get Bison to not accept (YYACCEPT?) something as a command until it reads ALL of the input. So I can have all these rules below that use recursion or whatever to build things up, which either results in a valid command or something that's not going to work. One simple test I'm doing with the code above is just entering "cd mydir mydir". Bison parses CD and WORD and goes "hey! this is a command, put it to the top!". Then the next token it finds is just WORD, which has no rule, and then it reports an error. I want it to read the whole line and realize CD WORD WORD is not a rule, and then report an error. I think I'm missing something obvious and would greatly appreciate any help - thanks! Also - I've tried using input command NEWLINE or something similar, but it still pushes CD WORD to the top as a command and then parses the extra WORD separately.

  Read the article

• why does this boost::spirit::qi rule not work?

  - by Tobias Langner

  I have a grammar that defines the following rules: constantValue = qi::token(ID_FLOAT) | qi::token(ID_INTEGER); postfixExpression = primaryExpression | (postfixExpression >> qi::token(ID_OPENBRACKET) >> qi::token(ID_INTEGER) >> qi::token(ID_CLOSEBRACKET)) | (postfixExpression >> qi::token(ID_DOT) >> qi::token(ID_IDENTIFIER)); primaryExpression = qi::token(ID_IDENTIFIER) | constantValue | (qi::token(ID_OPENPAREN) >> primaryExpression >> qi::token(ID_CLOSEPAREN)); ges = postfixExpression >> qi::eoi; and I want it to match the following strings: test[1] testident.ident and it should not match test[1.2] testident.5 but it fails to match the first 2 strings. The lexer constructor is as follows: custom_lexer() : identifier("[a-zA-Z_][a-zA-Z0-9_]*") , white_space("[ \\t\\n]+") , integer_value("[1-9][0-9]*") , hex_value("0[xX][0-9a-fA-F]+") , float_value("[0-9]*\\.[0-9]+([eE][+-]?[0-9]+)?") , float_value2("[0-9]+\\.([eE][+-]?[0-9]+)?") , punctuator("&>|\\*\\*|\\*|\\+|-|~|!|\\/|%|<<|>>|<|>|<=|>=|==|!=|\\^|&|\\||\\^\\^|&&|\\|\\||\\?|:|,")// [ ] ( ) . &> ** * + - ~ ! / % << >> < > <= >= == != ^ & | ^^ && || ? : , { using boost::spirit::lex::_start; using boost::spirit::lex::_end; this->self.add (identifier, ID_IDENTIFIER) /*(white_space, ID_WHITESPACE)*/ (integer_value, ID_INTEGER) (hex_value, ID_INTEGER) (float_value, ID_FLOAT) (float_value2, ID_FLOAT) ("\\(", ID_OPENPAREN) ("\\)", ID_CLOSEPAREN) ("\\[", ID_OPENBRACKET) ("\\]", ID_CLOSEBRACKET) ("\\.", ID_DOT) (punctuator, ID_PUNCTUATOR) ; this->self("WS") = white_space; } Why don't I get a match for the mentioned strings? Thank you Tobias

  Read the article

• How can I direct edge to get out of the diamond on the right?

  - by Didier Trosset

  I have a simple dot diagram to show how to perform tests. PerformTests; PerformTests<---+ PerformTests -> TestsPassed; | | TestsPassed [shape="diamond"]; v | TestsPassed -> Release [label="Yes"]; TestsPassed | TestsPassed -> FixErrors [label="No"]; Y| N\ | FixErrors -> PerformTests; v FixErrors Release The diagram shows square boxes for all nodes, except TestPassed that has a diamond shape. My issue is here. I'd like the edge that goes outside of the diamond for No to be getting out of the diamond at the right (east) instead of oblique down-right (south-east). What I have What I want ^ ^ / \ / \ < > < >---> \ /\ \ / v \ v I've seen such compass_pt in the dot grammar, but cannot figure out how to use it. I what I want possible, and how to do it?

  Read the article

< Previous Page | 12 13 14 15 16 17 18 19  | Next Page >