Reserved Identifier - 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 Identifier

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

    “Damn with faint praise, assent with civil leer,
    And, without sneering, teach the rest to sneer;
    Willing to wound, and yet afraid to strike,
    Just hint a fault, and hesitate dislike;
    Alike reserved to blame, or to commend,
    A timorous foe, and a suspicious friend;
    Dreading e’en fools, by flatterers besieged,
    And so obliging, that he ne’er obliged;
    Like Cato, give his little senate laws,
    And sit attentive to his own applause:”
    —Alexander Pope (1688–1744)

    “Even if society dictates that men and women should behave in certain ways, it is fathers and mothers who teach those ways to children—not just in the words they say, but in the lives they lead.”
    —Augustus Y. Napier (20th century)

    “English general and singular terms, identity, quantification, and the whole bag of ontological tricks may be correlated with elements of the native language in any of various mutually incompatible ways, each compatible with all possible linguistic data, and none preferable to another save as favored by a rationalization of the native language that is simple and natural to us.”
    —Willard Van Orman Quine (b. 1908)

    “To drive men from independence to live on alms, is itself great cruelty.”
    —Edmund Burke (1729–1797)