std.range.interfaces

This module is a submodule of std.range.

The main std.range module provides template-based tools for working with ranges, but sometimes an object-based interface for ranges is needed, such as when runtime polymorphism is required. For this purpose, this submodule provides a number of object and interface definitions that can be used to wrap around range objects created by the std.range templates.

InputRange Wrapper for input ranges.

InputAssignable Wrapper for input ranges with assignable elements.

ForwardRange Wrapper for forward ranges.

ForwardAssignable Wrapper for forward ranges with assignable elements.

BidirectionalRange Wrapper for bidirectional ranges.

BidirectionalAssignable Wrapper for bidirectional ranges with assignable elements.

RandomAccessFinite Wrapper for finite random-access ranges.

RandomFiniteAssignable Wrapper for finite random-access ranges with assignable elements.

RandomAccessInfinite Wrapper for infinite random-access ranges.

OutputRange Wrapper for output ranges.

OutputRangeObject Class that implements the OutputRange interface and wraps the

put methods in virtual functions.

outputRangeObject Convenience function for creating an OutputRangeObject with a base

range of type R that accepts types E.

InputRangeObject Class that implements the InputRange interface and wraps the

input range methods in virtual functions.

inputRangeObject Convenience function for creating an InputRangeObject

of the proper type.

MostDerivedInputRange Returns the interface type that best matches the range.

Source: std/range/interfaces.d

License

Boost License 1.0.

Authors

Andrei Alexandrescu, David Simcha, and

Jonathan M Davis. Credit for some of the ideas in building this module goes to Leonardo Maffi.

tmpl InputRangeObject MostDerivedInputRange outputRangeObject
class OutputRangeObject UnsupportedRangeMethod
iface BidirectionalAssignable BidirectionalRange ForwardAssignable ForwardRange InputAssignable InputRange OutputRange RandomAccessFinite RandomAccessInfinite RandomFiniteAssignable
fn inputRangeObject putMethods

Types 12

interfaceInputRange(E)

These interfaces are intended to provide virtual function-based wrappers around input ranges with element type E. This is useful where a well-defined binary interface is required, such as when a DLL function or virtual function needs to accept a generic range as a parameter. Note that isInputRange and friends check for conformance to structural interfaces not for implementation of these interface types.

Limitations:

These interfaces are not capable of forwarding ref access to elements.

Infiniteness of the wrapped range is not propagated.

Length is not propagated in the case of non-random access ranges.

See Also

inputRangeObject
Methods
E front() @property
E moveFront()Calls moveFront on the wrapped range, if possible. Otherwise, throws an UnsupportedRangeMethod exception.
void popFront()
bool empty() @property
int opApply(scope int delegate(E))`foreach` iteration uses opApply, since one delegate call per loop iteration is faster than three virtual function calls.
int opApply(scope int delegate(size_t, E))Ditto
interfaceForwardRange(E) : InputRange!E

Interface for a forward range of type E.

Methods
ForwardRange!E save() @property
interfaceBidirectionalRange(E) : ForwardRange!(E)

Interface for a bidirectional range of type E.

Methods
BidirectionalRange!E save() @property
E back() @property
E moveBack()Calls moveBack on the wrapped range, if possible. Otherwise, throws an UnsupportedRangeMethod exception
void popBack()
interfaceRandomAccessFinite(E) : BidirectionalRange!(E)

Interface for a finite random access range of type E.

Methods
RandomAccessFinite!E save() @property
E opIndex(size_t)
E moveAt(size_t)
size_t length() @property
interfaceRandomAccessInfinite(E) : ForwardRange!E

Interface for an infinite random access range of type E.

Fields
bool empty
Methods
E moveAt(size_t)Calls moveAt on the wrapped range, if possible. Otherwise, throws an UnsupportedRangeMethod exception.
RandomAccessInfinite!E save() @property
E opIndex(size_t)
interfaceInputAssignable(E) : InputRange!E

Adds assignable elements to InputRange.

Methods
void front(E newVal) @property
interfaceForwardAssignable(E) : InputAssignable!E, ForwardRange!E

Adds assignable elements to ForwardRange.

Methods
ForwardAssignable!E save() @property
interfaceBidirectionalAssignable(E) : ForwardAssignable!E, BidirectionalRange!E

Adds assignable elements to BidirectionalRange.

Methods
BidirectionalAssignable!E save() @property
void back(E newVal) @property
interfaceRandomFiniteAssignable(E) : RandomAccessFinite!E, BidirectionalAssignable!E

Adds assignable elements to RandomAccessFinite.

Methods
RandomFiniteAssignable!E save() @property
void opIndexAssign(E val, size_t index)
interfaceOutputRange(E)

Interface for an output range of type E. Usage is similar to the InputRange interface and descendants.

Methods
void put(E)
classOutputRangeObject(R, E...) : staticMap!(OutputRange, E)

Implements the OutputRange interface for all types E and wraps the put method for each type E in a virtual function.

Fields
private R _range
Constructors
this(R range)
classUnsupportedRangeMethod : Exception

Thrown when an interface method is not supported by the wrapped range

Functions 2

private fnstring putMethods(E...)()
fnInputRangeObject!R inputRangeObject(R)(R range) if (isInputRange!R)Convenience function for creating an `InputRangeObject` of the proper type. See InputRange for an example.

Templates 3

tmplMostDerivedInputRange(R) if (isInputRange!(Unqual!R))

Returns the interface type that best matches R.

tmplInputRangeObject(R) if (isInputRange!(Unqual!R))

Implements the most derived interface that R works with and wraps all relevant range primitives in virtual functions. If R is already derived from the InputRange interface, aliases itself away.

tmploutputRangeObject(E...)

Convenience function for creating an OutputRangeObject with a base range of type R that accepts types E.

Functions
OutputRangeObject!(R, E) outputRangeObject(R)(R range)