Cast from unknown type in c#
Basically your scenario is that you want to type cast with the type stored in a variable. You can only do that at runtime like this : myclass s=new myclass(); s.value = "10"; s.type = typeof(int); var val = Convert.ChangeType(s.value, s.type); but since the conversion is done at runtime, you...
what is the use of “static_cast” in macro?
This macro is designed to validate a certain real parameter passes a certain validation rule(s). The logic part of the macro is composed of 2 parts: Validate that param is a real parameter, with a valid name. This is done by using the static_cast, and if an illegal name is...
Program not compiling after casting pointer
c,pointers,casting,compiler-errors,void-pointers
This line: ptr = (struct sockaddr_in *) res->ai_addr; does not do what you think it does; it doesn't automagically make ptr be of type struct sockaddr_in *, so you're still trying to dereference a void pointer. What you need to do is printf("Port number: %u\n", ntohs(((struct sockaddr_in *) res->ai_addr)->sin_port)); ...
Difference between (float *) & *(float*) in C
The difference is You are dereferencing the int and casting it to float in printf("(float)* : %f\n", (float)*iptr); which is fine. You are casting the int pointer to a float pointer, and printing the float pointer with the "%f" specifier is undefined behavior, the correct specifier for printing pointers is...
Convert Nothing into Nullable(Of )
Is there a way to do so? Dim valueNothing = ConvertHelper.SafeChangeType(Of Boolean)(Nothing) Dim valueTrue = ConvertHelper.SafeChangeType(Of Boolean)(True) Dim valueFalse = ConvertHelper.SafeChangeType(Of Boolean)(False) ' ... Class ConvertHelper Shared Function SafeChangeType(Of T As Structure)(ByVal value As Object) As T? Return If(value Is Nothing, Nothing, DirectCast(Convert.ChangeType(value, GetType(T)), T?)) End Function End Class...
Is casting necessary in the following arithmetic sum?
For the case of short, the casts are unnecessary because short values are implicitly promoted to int in arithmetic expressions. For the other example, assuming int32 and int64 are what they seem to be, the cast is necessary if int is smaller than 64 bits. Technically, a single cast on...
converting varchar to Int SQL SERVER
The error is simply occurring as your destination column can only have one data type. The first part of your CASE statement is effictively setting the column type to expect an integer, so when you hit the ELSE section and try to insert Not Same, you're getting the error. Sample:...
Casting a String Into a Function in R
You can use parse() and eval(): foo <- eval(parse(text = function_code)) > foo function(x) { as.dist(1-cor(t(x))) } Just wrap that in a function: parseEval <- function(text) { eval(parse(text = text)) } If you need an actual something() rather than a direct call. Here's an example: set.seed(1) x <- matrix(runif(20), ncol...
type casting in objective-c, (NSInteger) VS. integerValue
NSNumber is a class; NSInteger is just a typedef of long, which is a primitive type. dic[@"count"] is a pointer, which means that dic[@"count"] holds an address that points to the NSNumber instance. NSNumber has a method called integerValue which returns an NSInteger as the underlying value that the NSNumber...
Can I determine the number of dimensions of a multi-dimensional list if it contains empty lists?
java,list,generics,multidimensional-array,casting
Am I worrying too much because all this stuff will be erased at runtime anyway? In a sense, yes - the method you've posted should work just as well with empty lists as with populated lists. Which isn't to say it will work well, but it won't have any...
Cast from generic to generic
You could use Convert's ChangeType-method: public Y get<Y>() { return (Y)Convert.ChangeType(data[pos], typeof(Y)); } It might also be a good idea to add some generic constraints to your class and method to ensure only primitives can be passed: class it<X> where X : struct public Y get<Y>() where Y : struct...
How to assign string to unsigned char[] in c++
Your sample code has either one or several problems with it if you are attempting to print out true. How many depends on how you're trying to do that. My first two points apply if you are comparing text to other text. If you're trying to convert text to a...
In a MySQL select statement, can I split a text column and then sum the parts as floats?
You may have to define your own function.Here is an example I just tested, hope it is helpful to you(BTW: It is not advisable to implement such kind of functions in mysql. Maybe it is better to let the application servers to compute it instead of mysql :)). DELIMITER $$...
Typecasting over a message queue in c
I think the problem is that you are passing an address that is on the stack, the int address cast as a char address. But that int location goes out of scope right after the send. One fix, if I'm right about that, would be to make the int location...
Cast from 'Int?' to unrelated type 'NSNumber' always fails
You can cast Int to NSNumber in this way let a:Int? = 10 let b = a! as NSNumber So,in your code,just try self.tv_salaryNumber.text = (earningsSoFar! as NSNumber).stringValue Also,as zeneak said,you can make it easier in his way...
Group By Date and SUM int - Date formatting and Order
sql-server,date,casting,order,group
If you really need to apply different formatting, you can do it using a derived table: select DATENAME(MM, [date]) + ' ' + CAST(DAY([date]) AS VARCHAR(2)) AS [DD Month], total_quantity from ( SELECT CAST([Datetime] AS DATE) AS [date], SUM(quantity) as total_quantity FROM Invoice_Itemized ii INNER JOIN Invoice_Totals it ON it.Invoice_Number...
Extract 2nd and 3rd value from char array and cast it as short (2 bytes). In C
t= *(short *)(a+1); You cast the pointer to the first element to a pointer-to-short, and then dereference it. Note that this is not very portable, and can go wrong if the machine is big endian or aligns data somehow. A better way would be: t = (a[2] << CHAR_BIT) |...
How to cast subclass object to superclass object
java,inheritance,casting,subclass,superclass
A superclass cannot know subclasses methods. Think about it this way: You have a superclass Pet You have two subclasses of Pet, namely: Cat, Dog Both subclasses would share equal traits, such as speak The Pet superclass is aware of these, as all Pets can speak (even if it doesn't...
Unwanted typecast in foreach
As arkascha said, htmlspecialchars and real_escape_string both return strings, it's kind of implied in the function of both. If you want ints, floats ect ect to return with the original datatype you'll just need to not perform the cleaning on them. It doesn't really make sense to try to escape...
(*var)[n] what does it mean in c++
(*var) means that var is a pointer variable, and it will indirect through the pointer to access the object it points to. Adding [n] means that it points to an array, and this will then access the nth element of the array. Don't confuse (*var)[n] with *var[n]. The latter is...
Unusual static_cast syntax
static_cast is not a function, it's a keyword, so the comma in a, b is not an argument separator; it is the comma operator. It evaluates a but throws away the result. The expression evaluates to b.
How can I convert an Int array into a String? array in Swift
ios,arrays,swift,casting,type-conversion
Airspeed Velocity gave you the answer: var arr: [Int] = [1,2,3,4,5] var stringArray = arr.map { String$($0) } Or if you want your stringArray to be of type [String?] var stringArray = arr.map { Optional(String$($0)) } This form of the map statement is a method on the Array type. It...
Virtual destructor of base class is not called when downcasting is done via dynamic cast
Your dynamic_cast fails in both cases, as you cannot safely downcast a Base to a Derived (your initial object is a Base, new Base). You should test the result of the dynamic cast if(!d1) // d1 is nullptr here std::cout << "Failed dynamic_cast"; Delete-ing a nullptr is a no-op, so...
Is this an unavoidable signed and unsigned integer comparison?
Cast the variables to a long int or long long int type giving at the same time the range of unsigned int (0..2^32-1) and sign.
Argument Type Problems
casting,compiler-errors,fortran
The value 1_Real32 is an int-literal-constant (R407, Fortran2008 4.4.2.2 5). To get a real value instead you need to change it to 1._Real32. The presence of the decimal makes it a real-literal-constant (R413, Fortran2008 4.4.2.3 6). Remember that Real32 in your code is just a number, e.g. 4 and it...
Base to derived class conversion does not result in null
c#,casting,subclass,base-class
the baseClass1 is an instance of Base, even though I used the Sub() constructor. That is totally not true. baseClass1 is an instance of Sub assigned to variable typed as Base. That's why you can cast it back to Sub....
Combobox Datasource assign to Datatable
vb.net,combobox,casting,datatable
I would use TryCast to get the job done. Dim dt As DataTable = TryCast(combobox1.DataSource, DataTable) If dt Is Nothing Then ' It didn't work because it's not a datatable ' Editors: I specifically did not reduce this expression ' to emphasize the need to check for 'Nothing' ' and...
Unable to use CAST Function
If you are using SQL Server 2012, you can use DATEFROMPARTS function to form a date, DateDiff to find the difference between two dates and finally cast(do you really have to??) your results to integer CAST(DATEDIFF(day, DATEFROMPARTS(2012,10,1 ), DateHired)/365 AS INTEGER) ...
Assigning a concrete Task to a variable of type Task
c#,inheritance,interface,casting,task-parallel-library
That is because this statement Task.Factory.StartNew(() => new Foo()); returns an instance of type Task<Foo>. And given that the Task<> class is a concrete class, it cannot be covariant, unless it were implementing a covariant interface (i.e. ITask<out T>). Note that there is a uservoice topic to do just that:...
cannot convert from int to byte [duplicate]
What you are failing to see is that a+b is a run-time operation whereas byte b = (int)8; is a compile-time operation. SO, during compile-time, the compiler knows that the constant 8 can be fit in a byte. So, the explicit conversion to (int) is ignored. The byte code will...
Java Interfaces Casting
C c = (C)i; Since i can hold instance of type C there is no problem with allowing by compiler casting I to C type reference (if casting will succeed at runtime we will be sure that all methods from C reference will be supported by instance which will...
F# cast / convert custom type to primitive
Your type CT32 is a Discriminated union with one case identifier CT32 of float. It's not an alias to float type so you couldn't just cast it to float. To extract the value from it you can use pattern matching (this is the easiest way). type CT32 = CT32 of...
In Java, How do I cast a Realm Object into the class I wish to write to the Database?
android,class,object,casting,realm
All Realm classes extends RealmObject so you can use generics to accomplish it: public static <T extends RealmObject> void executeInsertInto(final Context context, final T passedObject){ Realm realm = Realm.getInstance(context); realm.executeTransaction(new Realm.Transaction() { @Override public void execute(Realm realm) { T itemToWrite = realm.copyToRealm(passedObject); } }); realm.close(); } ...
What is the significance of (int*) in this program?
Casting is a way for a programmer to tell the computer that, even though the computer thinks something is one type, we want to treat it as another type. But here the cast is of no use as here a is an integer and thus address of a will need...
Automatic type casting while passing method parameters
Use following code to print 2D array: String deepToString(Object[] a) System.out.println(Arrays.deepToString(your2DArray)); Use below to print 1D array System.out.println(Arrays.toString(your1DArray)); ...
Casting error from deserialized json in c# using newton json
c#,json,serialization,casting,json.net
Because the type of deserializedData["key"] is Int64 (you'll see when you debug). You can't cast Int64 to int (Int32) . what you can do: int value = System.Convert.ToInt32(deserializedData["key"]); ...
calculation of limits of char without using macro definitions
The reason (char)((unsigned char)~0 >> 1) is 127 is obvious - You have 0xFFFFFFFF, cast it to unsigned char, you get 0xFF, shift by one and you have 0x7F or 127. The weird thing is why the first one is wrong: You cast a zero into unsigned char. Then you...
What is this type 'literal' syntax in Postgres?
postgresql,casting,postgresql-9.4
It is typed constant - see http://www.postgresql.org/docs/9.4/static/sql-syntax-lexical.html section 4.1.2.7. Constants of Other Types. A constant of an arbitrary type can be entered using any one of the following notations: type 'string' 'string'::type CAST ( 'string' AS type ) ...
Properly casting a `void*` to an integer in C++
I think using intptr_t is the correct intermediate here, since it's guaranteed to be large enough to contain the integral value of the void*, and once I have an integer value I can then truncate it without causing the compiler to complain. Yes, for the reason you mentioned that's...
Doubts about __bridge, _bridge_retain and _bridge_transfer
ios,objective-c,memory,types,casting
Your problem is that you're using a constant string. This is put straight into the programs memory so the reference is unexpectedly remaining valid despite the fact that it shouldn't. Use something less constant than a constant string and your program will brake like you think.
Need help to understand deserialization with ArrayList in Java
java,serialization,arraylist,casting,deserialization
It tells your that the compiler is unable to guarantee you that the cast would be successful in runtime - it may produce ClassCastException. Usually you are able to check type previously with instanceof to prevent this warning, e.g.: if (x instanceof ArrayList) { ArrayList y = (ArrayList) x; //...
Cast between unsigned and signed. How to?
char yourChar = 'a'; unsigned char yourUChar = static_cast<unsigned char>(yourChar); int yourInt = 1; unsigned int yourUInt = static_cast<unsigned int>(yourInt); A vector is just multiple ints, you'd cast each member in the vector. Same goes with a matrix. If you cast a signed value that has a negative value, to...
Different methods for casting an object in Java
The second method that you show is not casting; it's simply calling the toString() method on an object, which is not different than any other method call: String str2 = o.toString(); The effect of the first and third methods is essentially the same. I would prefer using the first method....
Cast button not displaying
android,casting,chromecast,google-cast
To answer your questions: As long as you do not need a custom or styled receiver and are fine with using the Default Receiver, then you do not need to register anything. If you register an app but do not publish that, then it will be visible to only those...
Downcasting doesn't work and functions called from object own class instead of where the function is (Java)
java,class,oop,methods,casting
When using inheritance within classes, overriding a method will ALWAYS call the child method regardless of casting. You can never change the type of an object, so a RockMusician - although it is an extension of Musician - is still a RockMusician and will be called by its type, not...
Cast map structure to void pointer and dereference
c++,dictionary,casting,void-pointers,dereference
In addToMap function you can cast the void pointer back to the original type: void addToMap(void *data){ auto pmap = static_cast<map<string, vector<myStruct> >*>(data); pmap->insert(...); } static_cast is also able to perform all conversions allowed implicitly (not only those with pointers to classes), and is also able to perform the opposite...
Python: Transform a unicode variable into a string variable
python,unicode,casting,web-crawler,unicode-string
Use a RegEx to extract the price from your Unicode string: import re def reducePrice(price): match = re.search(r'\d+', u' $500 ') price = match.group() # returns u"500" price = str(price) # convert "500" in unicode to single-byte characters. return price Even though this function converts Unicode to a "regular" string...
c: change variable type without casting
You could try union - as long as you make sure the types are identical in memory sizes: union convertor { int asInt; float asFloat; }; Then you can assign your int to asFloat (or the other way around if you want to). I use it a lot when I...
Safe and Efficient Type Punning in C++
Bit-wise arithmetic is well defined and perhaps more efficient. For this example: return seed ^ (seed >> 32); ...
the usage of the long double
If you are using the version of Code::Blocks with mingw, see this answer: Conversion specifier of long double in C mingw ... printf does not support the 'long double' type. Some more supporting documentation for it. http://bytes.com/topic/c/answers/135253-printing-long-double-type-via-printf-mingw-g-3-2-3-a If you went straight from float to long double, you may try just...
create utility to cast objects to beans in java
You're trying to cast your object to Class but I bet you intended to cast the object to the type that c represents. If so you should use Class.cast. For example: Class<String> c = String.class; String s = c.cast(o); If you want to return null in case it's the wrong...
Typecasting int to char, then search array
Use cast_number/*char*/ = (char) help_variable_remove_pv + '0'/*int*/; instead of cast_number/*char*/ = (char) help_variable_remove_pv/*int*/; A character and an integer somewhat are different. This means that '0'(character 0) and integer 0 aren't equal. You'll have to add 48 (ASCII value of '0') to 0 to get the integer value of '0'. See...
Java, store in byte higher value than 127
If I'm understanding your question, before you perform any calculations you need to AND (&) your bytes against 255, so you'll be dealing with values from 0 to 255 instead of -128 to 127. When you assign a value higher than 127 to a byte it overflows, so 128 as...
How to cast a compact type in Vala?
When you assign to an owned variable Vala has to copy the value (in this case the types aren't reference counted, so copying is the only way). The problem here is with the copying, not the casting. Assign it to an unowned variable: unowned GI.CallableInfo myCallableInfo = (GI.CallableInfo) myBaseInfo; ...
convert String to AnyObject in swift
From your examples and the error you see, you are attempting to unwrap a value that isn't optional. You don't need to use if let when there is a value. You can force a cast using if let like this: if let myValue:AnyObject = numb.selectedNumber as? AnyObject This will produce...
Label convert findcontrol
You are trying to assign Label to int, Label lbl = grdContact.Rows[e.RowIndex].FindControl("lblId_Row") as Label; if(lbl != null) { int id_row = int.Parse(lbl.Text); } ...
Java: must cast to short, cannot use shorthand 'S'
According to the Java Language Specification, Section 3.10.1, the only integer type suffix for integer literals is L (or lower case l). An integer literal is of type long if it is suffixed with an ASCII letter L or l (ell); otherwise it is of type int (§4.2.1). The suffix...
Casting a list of objects to another one
The return type of Read() is probably something like IEnumerable<Entity> or List<Entity>. That's why you can't cast them to a single Category. If you need a one line solution for this, you could try var categories = categoryDao.Read().OfType<Category>(); or (thanks @Binkan Salaryman) var categories = categoryDao.Read().Cast<Category>(); (the former will return...
Defining a “vector_cast” template function that works with a variable amount of nested vectors
With vector type detection you might do: #include <iostream> #include <vector> // is_vector // ========= namespace Detail { template<typename T> struct is_vector_test { static constexpr bool value = false; }; template<typename ... Types> struct is_vector_test<std::vector<Types...>> { static constexpr bool value = true; }; } template<typename T> struct is_vector : Detail::is_vector_test<typename...
Spring, Java : Passing Generic object List as return type
java,spring,spring-mvc,generics,casting
You should probably use a common interface shared by both classes. Declaring an interface like, for instance: public interface INotes{ } public class GroupNotes implements INotes{...} public class Notes implements INotes{...} Your code would become: @PreAuthorize("hasRole('ROLE_USER')") @RequestMapping(value = "/findnotebydays/{days}/{canvasid}/{mode}") public @ResponseBody List<INotes> findNotesByDays(@PathVariable("days")int days, @PathVariable("canvasid")int canvasid, @PathVariable("mode")boolean mode ){ if(!mode){...
What does *(*)() mean?
Yes, you're correct but I guess, this question needs a little more elaborated answer for why we are doing this. To start with, let's see what is done by the unary * operator. It dereferences it's operand based on the type of the operand. To elaborate in very simple terms,...
Inheritance and Casting error (generic interfaces)
c#,generics,casting,covariance
The problem is that new DataSeries<SimpleDataPoint> is not IDataSeries<IDataPoint>, because calling IDataSeries<IDataPoint>.Value = new AnotherDataPoint() and IDataPoint value = IDataSeries<IDataPointBase>.Value can fail. That is, runtime can't guarantee that what you're doing is type-safe, so it throws an exception to tell you that. Runtime can only guarantee one of these operations...
Getting the count (number of items) in a json response in swift
ios,json,swift,casting,afnetworking
By default, AFHTTPRequestOperationManager sets responseSerializer to an AFJSONResponseSerializer instance, so responseObject already is your parsed JSON set as Dictionary. Here is the code (refactored to remove some redundancy in casting and typing): func jsonLoaded(responseObject: AnyObject) { if let data = responseObject as? NSDictionary { let count = data.count print(count) for...
What is meant by this cast? (int (*)[10])
In my opinion, this is a "pointer to pointer to int". No. Its pointer to an array of 10 ints. Then I would assume that &array is of type (int (*)[10]) Yes. Your assumption is correct. &array is the address of array array and is of type int (*)[10]....
Is dynamic_casting through inheritance hierarchy bad practice?
There are a lot of questions on dynamic_cast here on SO. I read only a few and also don't use that method often in my own code, so my answer reflects my opinion on this subject rather than my experience. Watch out. (1.) Why is casting up/down considered bad design,...
How to cast generic parameter to generic interface?
c#,generics,casting,extension-methods
Change from IEnumerable<T> to the non generic IEnumerable (which the generic version inherits from anyway). public static IEnumerable<T> log_elements<T>(this IEnumerable<T> collection, bool recursive = true) { logElementsInternal(collection, recursive); return collection; } private static void logElementsInternal(IEnumerable collection, bool recursive) { Form1.log("["); foreach (var i in collection) if(recursive && i is IEnumerable)...
Cast sql_variant into data_type provided as varchar
sql,sql-server,stored-procedures,casting
Yes, you can pass sql_variants as parameters to sp_executesql, but you'll need to continue down the dynamic SQL route with the "Cast to" type, and use the name of the Type that you've determined for the column to be used in a CAST. Take this for example: CREATE TABLE Foo...
Objective C: Accessing properties of an object instance that's in an array that's a property of an object
ios,objective-c,osx,properties,casting
((Company*)myObject.companies[0]).myId Should do the trick...
How to split string in chars and get code of each char in freemarker?
You can't add numbers to characters in FreeMarker out-of-the-box. The closest thing is num?lower_abc (and n?upper_abc), which converts 1 to 'a', 2 to 'b', and so on. If you can't solve the task with that, and you can't add Java classes either, then this is going to be problem... Also,...
DB2 Convert from YYYYMMDD to Date
SELECT TIMESTAMP_FORMAT("DATEFIELD",'YYYYMMDD') as "MyDate"
When we typecast the int to double does the actual address where int is stored is get changed?
Casting doesn't affect the variable and the corresponding memory. It's just and indication for the compiler how to interpret the bits the reside at the given location. In Marcus'es example: int i = 12; double d = (double)i; d is a new variable in a completely new location. The original...
Possible to add a new class that can be cast to an existing final class?
Though B has all the methods and property dose A have, you can not cast object of B to a reference of A. That means - A a = (A) new B(); is invalid unless B extends A. And here A is a final class so you can not extends...
Template cast operator when T is QPointF
As far as I can tell the issue is that QPointF provides a constructor which takes a QPoint. When you do a static_cast the compiler tries to call QPointF(MyPoint&) and it sees two ways to create a QPointF from MyPoint: Use the constructor taking a QPoint, by converting MyPoint to...
Java: Implementing an interfacing by inheriting a class
java,inheritance,interface,casting
In a class where we use an instance of A (referenced as A), it is cast to a B Reference so that we can use a Method defined in class B. So I'm assuming you have this scenario public void doStuff(A aType){ ... B bType = (B) aType; ......
Google coding challenge not detecting int
It's telling you that it is expecting to find a method that takes an int parameter, but you have declared your method to take a long. While you can pass an int to a method that's expecting a long, the method signature is different, and so the expected signature is...
C++ - Safety of reinterpret_cast for pointer-to-primitives
c++,casting,type-safety,reinterpret-cast
No it is not safe: the program behaviour is undefined. This is because the pointer types are unrelated....
Converting String into NSDate in array of dictionaries
arrays,swift,casting,nsdate,nsdictionary
I dont know how you set up things before this little snippet in you question but this is how I did: var arr:[[String:AnyObject]] = [["id":1, "planning_id":2, "started_on":"2015-05-13"], ["id":1, "planning_id":2, "started_on":"2015-05-14"], ["id":1, "planning_id":2, "started_on":"2015-05-10"]] for (i, dict) in enumerate(arr) { let dateString = dict["started_on"] as! String let formatter = NSDateFormatter() formatter.dateFormat...
Is std::string::npos == -1 always true?
NO, it is not always true. It is however a bit more complicated than it seems at first glance: In the beginning, let us see what std::string is (21.3/1): The header <string> defines the basic_string class template for manipulating varying-length sequences of char-like objects and four typedefs, string, u16string, u32string,...
Cast StringCollection as List [duplicate]
They are string values, you can't cast string to int. You need to Convert/Parse it like: parameters[parameters.FindIndex(x => x.Name == "IDs")].Values .Cast<String>() //So that LINQ could be applied .Select(int.Parse) .ToList() You need .Cast<String>() so that you can apply LINQ on the StringCollection. ...
fn:sum error “cannot cast to xs:double”
You can try this way : for $x in //onboard/*[*] return sum($x/*) That reads : for $x as each child of <onboard> having at least one child element, return sum of all children element of $x. UPDATE : Turned out that the problem was due to empty element(s) passed to...
R is passing list index value as numeric, how to force pass as characters
The error is cList is a list, so you can cast it directly to character the component you get with cList[i], because this is also a list! If you have myList = list(a=1, b=2, c=3), myList[1] and myList[1:2] are lists (try class(myList[1]) and class(myList[1:2]) to check). On the other hand,...
For what reason printf does not correctly display the float?
c,casting,floating-point,printf
7 / 3 without a cast is integer division, resulting in the integer 2, since any remainder is discarded, so it is equivalent of calling printf("%0.2f\n", 2); Now, why does that print 0 instead of 2? Well, you told it it is a float in the format string ("%0.2f"). So...
Postgres return null values on function error/failure when casting
sql,postgresql,casting,plpgsql
This can be done by trapping an exception in a plpgsql function. create or replace function my_to_timestamp(arg text) returns timestamp language plpgsql as $$ begin begin return arg::timestamp; exception when others then return null; end; end $$; select id, c1, my_to_timestamp(c1) as c2 from a; Trying to define a generic...
final casting concept doesn't apply for overloading
java,casting,method-overloading
You are mixing up memory space of variables and their type. Calling the method m(...) will first of all check the type of the paramether variable. Here it is an int so it will chose the according overloaded method, no matter the size of the int in memory. Although I...
Casting a pointer by reference
c++,casting,parameter-passing,pass-by-reference
In the first example, you're actually passing the pointer variable b. So it works. In the second example, the first reinterpret_cast returns a pointer (by value), which doesn't match the reference the function should get, while the second returns said reference. As an example to show you how references work,...
Typecasting vs function to convert variable type in PHP
There's no difference in the resulting value, just: (float) is a language feature and very quick floatval() incurs the overhead of a function call (minimal, but nonetheless...) floatval() as a function can be used in ways that (float) cannot, e.g. array_map('floatval', $foo) The last point is, I believe, the main...
Cannot convert int {Class}::* to int*
Change to: class MyClass { public: static const int MAJOR = 3; static const int MINOR = 3; static const int REV = 0; }; If these versions are constant. Otherwise as: class MyClass { public: static int MAJOR; static int MINOR; static int REV; }; Then somewhere in a...
how divided integer is converted to floating point number with decimal [duplicate]
The cast does not apply to the entire expression 123/33. You're casting the value 123 to a float, which causes any further operations to use floating-point math.
Unconstrained type parameters casting
The compiler sees the T2 and T identifiers and helpfully informs you that those types seem unrelated. That's absolutely correct, as they have no relation: there are no generic constraints that would assert any relations between them (I'm not saying that would be useful here though :) ). Whether this...
Avoid Type Casting During Data Processing
java,oop,inheritance,design,casting
At the end of the day, you're branching based on the subtype (concrete classes) since the logic to validate user input is based on those specific details contained in the subclasses. Generics don't really help you much here since generics are based primarily on applying logic that is uniform across...
Google Cast Media Player Library - for streaming from Local Device
ios,casting,chromecast,google-cast
This is a piece of the definition given there: ... It provides JavaScript support for parsing manifests and playing HTTP Live Streaming (HLS), MPEG-DASH, and Smooth Streaming content. It also provide support for HLS AES encryption, PlayReady DRM, and Widevine DRM. I hope this is not ambiguous; if your media...
Scala generic cast from String function
I don't think there is a way to write the function as such with Manifest, ClassTag or a TypeTag as they can only tell you the type at runtime. For something like the pseudocode function to work, the return type must be known at compile time. However, could implement the...