rsc3/doc-schelp/HelpSource/Classes/EnvironmentRedirect.scrbl

76 lines
2.1 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{EnvironmentRedirect}
base class for environment redirects@section{categories}
Libraries>JITLib>Environments, Collections>Unordered, Live Coding
@section{related}
Classes/Environment
@section{description}
Environment that redirects access (strong::put::) and assignment (strong::at::). It is used as a base class for redirecting Environments. For example uses, see link::Classes/LazyEnvir:: and link::Classes/ProxySpace::.
@section{ClassMethods}
@section{method}
new
Create new environment redirect, if envir is given, it is used as a basis.
@section{subsection}
replacing Environment class methods
EnvironmentRedirect implements some of the interface of link::Classes/Environment::
@section{method}
push, pop, make, use
@section{InstanceMethods}
@section{method}
envir
return or replace the source environment
@racketblock[
e = LazyEnvir.new;
e.put(\x, 9);
e.envir; // look into the envir itself: for a LazyEnvir it contains Maybe as placeholders
::
]
@section{subsection}
redirecting objects
Overriding these methods, one can redirect where objects go when they are assigned to the space. This is done for example in link::Classes/LazyEnvir:: and link::Classes/ProxySpace::.
@section{method}
at, put, localPut, removeAt
@section{method}
dispatch
A function or object that is called when the environment is modified. The key and the changed object are passed as arguments.
@racketblock[
e = LazyEnvir.new;
e.dispatch = { |key, val| [key, val].postln };
e.put(\x, 9);
::
]
@section{subsection}
replacing Environment instance methods
EnvironmentRedirect implements some of the interface of link::Classes/Environment::, which it can replace where needed.
@section{method}
push, pop, make, use, do, clear, keysValuesDo, keysValuesArrayDo, findKeyForValue, sortedKeysValuesDo, choose, know, doesNotUnderstand
@section{section}
Networking
EnvironmentRedirect and its subclasses can be used to dispatch assignment over a network. To do this, a dispatch function can be supplied - see Public in strong::JITLibExtensions:: quark.