String (computer science): Difference between revisions

Revision as of 01:49, 28 May 2002

Revision as of 08:46, 28 May 2002

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=== Representations ===

A common representation is an [[array]] of characters. The length can be stored implicitly by using a special terminating character (often [[NUL]]) (the programming language [[C programming language|C]] uses this convention), or explicitly (for example by treating the first byte or bytes of the string as its length, a convention used in [[Pascal programming language|Pascal]]).

Here is a NUL terminated string stored in a 10 [[Integral data types|byte]] buffer.
NUL is the name for the character in [[ASCII]] which has the numeric value of zero.

In the C language, NUL is called '\0'.

<PRE>

x x x x x x x x x x

F R A N K \0 k f f w

x x x x x x x x x x

</PRE>

The above example is how "FRANK" would look in a 10 byte NUL terminated string. Characters after the \0 do not form part of the representation.

Of course, other representations are possible. Using [[tree]]s and [[list]]s make it easier to insert characters in the middle of the string.