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)

    “I wish our clever young poets would remember my homely definitions of prose and poetry; that is, prose = words in their best order;Mpoetry = the best words in the best order.”
    —Samuel Taylor Coleridge (1772–1834)

    “I invented the colors of the vowels!—A black, E white, I red, O blue, U green—I made rules for the form and movement of each consonant, and, and with instinctive rhythms, I flattered myself that I had created a poetic language accessible, some day, to all the senses.”
    —Arthur Rimbaud (1854–1891)

    “In England the judges should have independence to protect the people against the crown. Here the judges should not be independent of the people, but be appointed for not more than seven years. The people would always re-elect the good judges.”
    —Andrew Jackson (1767–1845)