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:

    “From a hasty glance through the various tests I figure it out that I would be classified in Group B, indicating “Low Average Ability,” reserved usually for those just learning to speak the English Language and preparing for a career of holding a spike while another man hits it.”
    —Robert Benchley (1889–1945)

    “Like a tale of little meaning though the words are strong;
    Chanted from an ill-used race of men that cleave the soil,
    Sow the seed, and reap the harvest with enduring toil,
    Storing yearly little dues of wheat, and wine and oil;
    Till they perish and they suffer—some, ‘tis
    whispered—down in hell”
    —Alfred Tennyson (1809–1892)

    “This is an approach to that universal language which men have sought in vain.”
    —Henry David Thoreau (1817–1862)

    “A tragic irony of life is that we so often achieve success or financial independence after the chief reason for which we sought it has passed away.”
    —Ellen Glasgow (1873–1945)