Exception

The base class of all errors that are safe to catch and handle.

In principle, only thrown objects derived from this class are safe to catch inside a catch block. Thrown objects not derived from Exception represent runtime errors that should not be caught, as certain runtime guarantees may not hold, making it unsafe to continue program execution.

class Exception : Throwable {

this(string msg, string file = __FILE__, size_t line = __LINE__, Throwable nextInChain = null);

}

Constructors

this this(string msg, string file = __FILE__, size_t line = __LINE__, Throwable nextInChain = null): Creates a new instance of Exception. The nextInChain parameter is used internally and should always be null when passed by user code. This constructor does not automatically throw the newly-created Exception; the throw statement should be used for that purpose.

Inherited Members

From Throwable

file string file;: The file name of the D source code corresponding with where the error was thrown from.
line size_t line;: The line number of the D source code corresponding with where the error was thrown from.
info TraceInfo info;: The stack trace of where the error happened. This is an opaque object that can either be converted to string, or iterated over with foreach to extract the items in the stack trace (as strings).
next inout(Throwable) next()
next void next(Throwable tail): Replace next in chain with tail. Use chainTogether instead if at all possible.
refcount uint refcount()
opApply int opApply(scope int delegate(Throwable) dg): Loop over the chain of Throwables.
chainTogether Throwable chainTogether(return scope Throwable e1, return scope Throwable e2): Append e2 to chain of exceptions that starts with e1.
toString string toString(): Overrides Object.toString and returns the error message. Internally this forwards to the toString overload that takes a sink delegate.
toString void toString(scope void delegate(in char[]) sink): The Throwable hierarchy uses a toString overload that takes a _sink delegate to avoid GC allocations, which cannot be performed in certain error situations. Override this toString method to customize the error message.
message const(char)[] message(): Get the message describing the error. Base behavior is to return the Throwable.msg field. Override to return some other error message.

Examples

1 bool gotCaught;
2 try
3 {
4     throw new Exception("msg");
5 }
6 catch (Exception e)
7 {
8     gotCaught = true;
9     assert(e.msg == "msg");
10 }
11 assert(gotCaught);

object classes

functions

structs

templates

RTInfoImpl

variables

rtinfoNoPointers