Difference between revisions of "Control flow"

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'''Control flow''' refers to the means for controlling the order in which sections of a [[program]] are executed.
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'''Control flow''' refers to the means for controlling the order in which sections of a [[program]] are [[execute]]d.
  
The underlying [[Central Processing Unit|CPU]]'s [[instruction set]] will have a number of '''transfer of control''' primitives: jump/branch, both un-conditional as well as [[conditional branch]]es; and [[subroutine]] calls.
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The underlying [[Central Processing Unit|CPU]]'s [[instruction set]] will have a number of '''transfer of control''' primitives: [[jump]]/branch, both un-conditional as well as [[conditional branch]]es; and [[subroutine]] calls.
  
 
[[Programming language]]s often add additional mechanisms, particularly '''block structures''', in which a group of instructions are treated as a unit for various control flow mechanisms (e.g. [[loop]]s, if-then-else constructs, etc).
 
[[Programming language]]s often add additional mechanisms, particularly '''block structures''', in which a group of instructions are treated as a unit for various control flow mechanisms (e.g. [[loop]]s, if-then-else constructs, etc).

Latest revision as of 14:31, 13 August 2019

Control flow refers to the means for controlling the order in which sections of a program are executed.

The underlying CPU's instruction set will have a number of transfer of control primitives: jump/branch, both un-conditional as well as conditional branches; and subroutine calls.

Programming languages often add additional mechanisms, particularly block structures, in which a group of instructions are treated as a unit for various control flow mechanisms (e.g. loops, if-then-else constructs, etc).

Blocks are also often used to control the scope over which variables (particularly local variables) are accessible.

Interrupts and exceptions also divert the flow of control in a computer, but at times which are not always predictable.