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Programming Ruby The Pragmatic Programmer's Guide |
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class Binding
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Parent:
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Object
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Version:
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1.6
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Index:
Objects of class Binding encapsulate the execution context at some
particular place in the code and retain this context for future use.
The variables, methods, value of self, and possibly an iterator
block that can be accessed in this context are all retained.
Binding objects can be created using
Kernel#binding
, and are
made available to the callback of
Kernel#set_trace_func
.
These binding objects can be passed as the second argument of the
Kernel#eval
method, establishing an environment for the
evaluation.
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class Demo
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def initialize(n)
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@secret = n
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end
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def getBinding
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return binding()
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end
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end
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k1 = Demo.new(99)
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b1 = k1.getBinding
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k2 = Demo.new(-3)
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b2 = k2.getBinding
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eval("@secret", b1)
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99
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eval("@secret", b2)
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-3
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eval("@secret")
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nil
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Binding objects have no class-specific methods.
Extracted from the book "Programming Ruby -
The Pragmatic Programmer's Guide"
Copyright
©
2001 by Addison Wesley Longman, Inc. This material may
be distributed only subject to the terms and conditions set forth in
the Open Publication License, v1.0 or later (the latest version is
presently available at http://www.opencontent.org/openpub/)).
Distribution of substantively modified versions of this document is
prohibited without the explicit permission of the copyright holder.
Distribution of the work or derivative of the work in any standard
(paper) book form is prohibited unless prior permission is obtained
from the copyright holder.
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