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std
 std.base64
 std.boxer
 std.compiler
 std.conv
 std.ctype
 std.date
 std.file
 std.format
 std.gc
 std.intrinsic
 std.math
 std.md5
 std.mmfile
 std.openrj
 std.outbuffer
 std.path
 std.process
 std.random
 std.recls
 std.regexp
 std.socket
 std.socketstream
 std.stdint
 std.stdio
 std.cstream
 std.stream
 std.string
 std.system
 std.thread
 std.uri
 std.utf
 std.zip
 std.zlib

std.windows

std.linux

std.c
 std.c.stdio

std.c.windows

std.c.linux

std.boxer

This module is a set of types and functions for converting any object (value or heap) into a generic box type, allowing the user to pass that object around without knowing what's in the box, and then allowing him to recover the value afterwards.

Example


    // Convert the integer 45 into a box.
    Box b = box(45);
    
    // Recover the integer and cast it to real.
    real r = unbox!(real)(b);
    

That is the basic interface and will usually be all that you need to understand. If it cannot unbox the object to the given type, it throws UnboxException. As demonstrated, it uses implicit casts to behave in the exact same way that static types behave. So for example, you can unbox from int to real, but you cannot unbox from real to int: that would require an explicit cast.

This therefore means that attempting to unbox an int as a string will throw an error instead of formatting it. In general, you can call the toString method on the box and receive a good result, depending upon whether std.string.format accepts it.

Boxes can be compared to one another and they can be used as keys for associative arrays.

There are also functions for converting to and from arrays of boxes.

Example


    // Convert arguments into an array of boxes.
    Box[] a = boxArray(1, 45.4, "foobar");
    
    // Convert an array of boxes back into arguments.
    TypeInfo[] arg_types;
    void* arg_data;
    
    boxArrayToArguments(a, arg_types, arg_data);
    
    // Convert the arguments back into boxes using a
    // different form of the function.
    a = boxArray(arg_types, arg_data);
    

One use of this is to support a variadic function more easily and robustly; simply call "boxArray(_arguments, _argptr)", then do whatever you need to do with the array.

struct Box
Box is a generic container for objects (both value and heap), allowing the user to box them in a generic form and recover them later.

TypeInfo type
Property for the type contained by the box. This is initially null and cannot be assigned directly.

void* data
Property for the data pointer to the value of the box. This is initially null and cannot be assigned directly.

bit unboxable(TypeInfo type)
Return whether the value could be unboxed as the given type without throwing an error.

char[] toString()
Attempt to convert the boxed value into a string using std.string.format; this will throw if that function cannot handle it. If the box is uninitialized then this returns "".

bit opEquals(Box other)
Compare this box's value with another box. This implicitly casts if the types are different, identical to the regular type system.

float opCmp(Box other)
Compare this box's value with another box. This implicitly casts if the types are different, identical to the regular type system.

uint toHash()
Return the value's hash.

Box box(...)
Box the single argument passed to the function. If more or fewer than one argument is passed, this will assert.

Box box(TypeInfo type, void* data)
Box the explicitly-defined object. type must not be null; data must not be null if the type's size is greater than zero.

Box[] boxArray(TypeInfo[] types, void* data)
Box[] boxArray(...)
Convert a list of arguments into a list of boxes.

void boxArrayToArguments(Box[] arguments, out TypeInfo[] types, out void* data)
Convert a list of boxes into a list of arguments.

bit unboxable!(T)(Box value)
Return whether the value can be unboxed as the given type; if this returns false, attempting to do so will throw UnboxException.

T unbox!(T)(Box value)
This template function converts a boxed value into the provided type. To use it, instantiate the template with the desired result type, and then call the function with the box to convert.

This will implicitly cast base types as necessary and in a way consistent with static types - for example, it will cast a boxed byte into int, but it won't cast a boxed float into short. If it cannot cast, it throws UnboxException.

Example


    Box b = box(4.5);
    bit u = unboxable!(real)(b); // This is true.
    real r = unbox!(real)(b);
    

class UnboxException : Error
This class is thrown if unbox is unable to cast the value into the desired result.

this(Box object, TypeInfo outputType)
Assign parameters and create the message in the form "Could not unbox from type to ."

box object
This is the box that the user attempted to unbox.

TypeInfo outputType
This is the type that the user attempted to unbox the value as.

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