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Lexical Scope
`Lexical Scope' defines the access to variables
within functions. Variables within functions are either
`lambda-bound' or `free'.
The `lambda-bound' variables refer to arguments passed to
the function.
The so-called `free' variables must have been defined
in the inherited environment of the function.
In a language with `Lexical Scope' a lambda abstraction inherits
all variables from those abstractions in which it is defined.
`Lexical Scope' in A++ is coupled with indefinite extent
in contrast to Pascal where 'Lexical Scope' is coupled with
`limited extent'.
`Lexical Scope' regulates the access to variables in a
lambda-abstraction by its context visible in the program text.
Georg P. Loczewski
2004-03-05