Eggs Unlimited

Description

Boxing

Author

Kon Lovett

Usage

(require-extension box)

Download

box.egg

Documentation

Boxed Values

The read and print syntax for a box is #&object where object is the contents of the box. However, only mutable boxes will be recovered. An immutable or variable box will lose identity when printed.

procedure: (make-box [INITIAL-VALUE [#:immutable? #f]])

Returns a box with the optional INITIAL-VALUE. The #:immutable? parameter does what it says.

macro: (make-box-variable VARIABLE [#:immutable? #f])

Returns a boxed reference to the variable VARIABLE, which must be in lexical-scope.

macro: (make-box-location TYPE [INITIAL-VALUE [#:immutable? #f]])

Returns a boxed reference to a location variable of TYPE, with optional INITIAL-VALUE and #:immutable? parameters as make-box.

Note this macro can only be used in compiled source!

procedure: (box? BOX)

Is it a box?

procedure: (box-mutable? BOX)

Is it a mutable box?

procedure: (box-immutable? BOX)

Is it an immutable box?

procedure: (box-variable? BOX)

Is it a boxed variable?

procedure: (box-set! BOX VALUE)

Sets the boxed value to VALUE.

procedure: (box-ref BOX)

Returns the boxed value.

procedure: (box-location BOX)

Returns the location of the boxed value.

MzScheme-Like

Needs (use box-mzs).

macro: (box INITIAL-VALUE)

Returns a box with the INITIAL-VALUE.

macro: (box-immutable VALUE)

Returns a box with the VALUE. Signals an error upon attempted set.

macro: (box-variable VARIABLE)

Returns a boxed reference to the variable VARIABLE, which must be in lexical-scope.

macro: (set-box! BOX VALUE)

Sets the boxed value to VALUE.

macro: (unbox BOX)

Returns the boxed value.

Version

1.9 No checks.
1.8 Bugfix for immutable? keyword argument handling.
1.7 Added immutable? keyword argument, 'make-box-location', and 'box-location'.
1.6 Slightly smaller, print syntax
1.5 #& box read syntax
1.4 box-ref/set! now procedures
1.3 Exports
1.2 Added MzScheme-like box api, changed references
1.1 Added references, different implementation of box
1.0 Initial release

License

Copyright (c) 2006, Kon Lovett.  All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the Software),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ASIS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.