Reserved Word - Reserved Words and Language Independence

Reserved Words and Language Independence

Microsoft’s .NET Common Language Infrastructure (CLI) specification allows code written in 40+ different programming languages to be combined together into a final product. Because of this, identifier/reserved word collisions can occur when code implemented in one language tries to execute code written in another language. For example, a Visual Basic.NET library may contain a class definition such as:

' Class Definition of This in Visual Basic.NET: Public Class this ' This class does something... End Class

If this is compiled and distributed as part of a toolbox, a C# programmer, wishing to define a variable of type “this” would encounter a problem: 'this' is a reserved word in C#. Thus, the following will not compile in C#:

// Using This Class in C#: this x = new this; // Won't compile!

A similar issue arises when accessing members, overriding virtual methods, and identifying namespaces.

In order to work around this issue, the specification allows the programmer to (in C#) place the at-sign before the identifier which forces it to be considered an identifier rather than a reserved word by the compiler.

// Using This Class in C#: @this x = new @this; // Will compile!

For consistency, this usage is also permitted in non-public settings such as local variables, parameter names, and private members.

Read more about this topic:  Reserved Word

Famous quotes containing the words reserved, words, language and/or independence:

    The final flat of the hoe’s approval stamp
    Is reserved for the bed of a few selected seed.
    Robert Frost (1874–1963)

    Rather than words comes the thought of high windows:
    The sun-comprehending glass,
    And beyond it, the deep blue air, that shows
    Nothing, and is nowhere, and is endless.
    Philip Larkin (1922–1986)

    Repeat thy song, till the familiar lines
    Are footpaths for the thought of Italy!
    Thy flame is blown abroad from all the heights,
    Through all the nations, and a sound is heard,
    As of a mighty wind, and men devout,
    Strangers of Rome, and the new proselytes,
    In their own language hear thy wondrous word,
    And many are amazed and many doubt.
    Henry Wadsworth Longfellow (1809–1882)

    We commonly say that the rich man can speak the truth, can afford honesty, can afford independence of opinion and action;—and that is the theory of nobility. But it is the rich man in a true sense, that is to say, not the man of large income and large expenditure, but solely the man whose outlay is less than his income and is steadily kept so.
    Ralph Waldo Emerson (1803–1882)