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Module `std.exception`

This module defines functions related to exceptions and general error handling. It also defines functions intended to aid in unit testing.

Synopsis of some of std.exception's functions:

string synopsis()
{
    FILE* f = enforce(fopen("some/file"));
    // f is not null from here on
    FILE* g = enforce!WriteException(fopen("some/other/file", "w"));
    // g is not null from here on

    Exception e = collectException(write(g, readln(f)));
    if (e)
    {
        ... an exception occurred...
        ... We have the exception to play around with...
    }

    string msg = collectExceptionMsg(write(g, readln(f)));
    if (msg)
    {
        ... an exception occurred...
        ... We have the message from the exception but not the exception...
    }

    char[] line;
    enforce(readln(f, line));
    return assumeUnique(line);
}

Functions

Name	Description
`assertNotThrown`	Asserts that the given `expression` does not throw the given type of `Throwable`. If a `Throwable` of the given type is thrown, it is caught and does not escape `assertNotThrown`. Rather, an `AssertError` is thrown. However, any other `Throwable`s will escape.
`assertThrown`	Asserts that the given `expression` throws the given type of `Throwable`. The `Throwable` is caught and does not escape `assertThrown`. However, any other `Throwable`s will escape, and if no `Throwable` of the given type is thrown, then an `AssertError` is thrown.
`assumeUnique`	Casts a mutable `array` to an immutable `array` in an idiomatic manner. Technically, `assumeUnique` just inserts a cast, but its name documents assumptions on the part of the caller. `assumeUnique(arr)` should only be called when there are no more active mutable aliases to elements of `arr`. To strengthen this assumption, `assumeUnique(arr)` also clears `arr` before returning. Essentially `assumeUnique(arr)` indicates commitment from the caller that there is no more mutable access to any of `arr`'s elements (transitively), and that all future accesses will be done through the immutable `array` returned by `assumeUnique`.
`assumeWontThrow`	Wraps a possibly-throwing expression in a `nothrow` wrapper so that it can be called by a `nothrow` function.
`collectException`	Catches and returns the exception thrown from the given `expression`. If no exception is thrown, then null is returned and `result` is set to the `result` of the `expression`.
`collectException`	Catches and returns the exception thrown from the given `expression`. If no exception is thrown, then null is returned. `E` can be `void`.
`collectExceptionMsg`	Catches the exception thrown from the given `expression` and returns the msg property of that exception. If no exception is thrown, then null is returned. `E` can be `void`.
`doesPointTo`	The "pointsTo" functions, `doesPointTo` and `mayPointTo`.
`enforce`	If `!!value` is true, `value` is returned. Otherwise, `new Exception(msg)` is thrown.
`enforce`	Deprecated. If passing the file or line number explicitly, please use the overload of `enforce` which takes them as function arguments. Taking them as template arguments causes unnecessary template bloat. This overload will be removed in June 2015.
`enforce`	If `!!value` is true, `value` is returned. Otherwise, the given delegate is called.
`enforce`	If `!!value` is true, `value` is returned. Otherwise, `ex` is thrown.
`errnoEnforce`	If `!!value` is true, `value` is returned. Otherwise, `new ErrnoException(msg)` is thrown. `ErrnoException` assumes that the last operation set `errno` to an error code.
`handle`	Handle exceptions thrown from range primitives.
`ifThrown`	ML-style functional exception handling. Runs the supplied `expression` and returns its result. If the `expression` throws a `Throwable`, runs the supplied error handler instead and return its result. The error handler's type must be the same as the `expression`'s type.

Classes

Name	Description
`ErrnoException`	Thrown if errors that set `errno` occur.

Enums

Name	Description
`RangePrimitive`	This `enum` is used to select the primitives of the range to `handle` by the `handle` range wrapper. The values of the `enum` can be `OR`'d to select multiple primitives to be handled.

Templates

Name	Description
`enforceEx`	If `!!value` is `true`, `value` is returned. Otherwise, `new E(msg, file, line)` is thrown. Or if `E` doesn't take a message and can be constructed with `new E(file, line)`, then `new E(file, line)` will be thrown.

Enum values

Name	Type	Description
`emptyExceptionMsg`		Value that `collectExceptionMsg` returns when it catches an exception with an empty exception message.

Module `std.exception`

Functions

Classes

Enums

Templates

Enum values

Authors

License

Comments

Module std.exception

Functions

Classes

Enums

Templates

Enum values

Authors

License

Comments

Module `std.exception`