In
computer programming, a control variable is a
program variable
In computer programming, a variable is an abstract storage location paired with an associated symbolic name, which contains some known or unknown quantity of information referred to as a '' value''; or in simpler terms, a variable is a named con ...
that is used to regulate the
flow of control
In computer science, control flow (or flow of control) is the order in which individual statements, instructions or function calls of an imperative program are executed or evaluated. The emphasis on explicit control flow distinguishes an ''im ...
of the program.
In definite iteration, control variables are variables which are successively assigned (or bound to) values from a predetermined sequence.
Special rules
In some programming languages, control variables are just ordinary variables used for manipulating the program flow. This is the case of
C,
Fortran, and
Pascal, which allow for control variables to have their values changed within the loop body.
However, some languages have special rules for control variables. In
Ada, for instance, the control variable of a
for-loop
In computer science a for-loop or for loop is a control flow statement for specifying iteration. Specifically, a for loop functions by running a section of code repeatedly until a certain condition has been satisfied.
For-loops have two part ...
must remain constant within the loop body.
References
Mathematical terminology
Computing terminology
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