Programming Ruby: The Pragmatic Programmer's Guide

# Programming Ruby ### The Pragmatic Programmer's Guide
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class Binding |
Parent: | Object
Version: | 1.6

### 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.

`class Demo`
`def initialize(n)`
`@secret = n`
`end`
`def getBinding`
`return binding()`
`end`
`end`
``
`k1 = Demo.new(99)`
`b1 = k1.getBinding`
`k2 = Demo.new(-3)`
`b2 = k2.getBinding`
``
`eval("@secret", b1)` | » | `99`
`eval("@secret", b2)` | » | `-3`
`eval("@secret")` | » | `nil`

Binding objects have no class-specific methods.

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Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
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