Difference between revisions of "Exception"

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An '''exception''' (more often '''condition''') refers to facilities in some [[programming language]]s and [[operating system]]s to indicate the occurrence of some sort of error or un-expected event - e.g. 'divide by zero' or 'unexpected end-of-file'.
 
An '''exception''' (more often '''condition''') refers to facilities in some [[programming language]]s and [[operating system]]s to indicate the occurrence of some sort of error or un-expected event - e.g. 'divide by zero' or 'unexpected end-of-file'.
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The term 'exception' is also often used for hardware-detected issues (e.g. in the [[Motorola 68000 Family]]), where a [[trap]] is the usual result; the term 'condition' is usually more general, and covers software-detected and generated issues. Software is said to '''raise''' or '''signal''' a condition.
  
 
When such an event happens, program execution is diverted to an [[condition handler]] for that specific condition, which is expected to deal with that condition.
 
When such an event happens, program execution is diverted to an [[condition handler]] for that specific condition, which is expected to deal with that condition.
 
The term 'exception' is also often used for hardware-detected issues (e.g. in the [[Motorola 68000 Family]]), where a [[trap]] is the usual result; the term 'condition' is usually more general, and covers software-detected and generated issues. Software is said to '''raise''' or '''signal''' a condition.
 
  
 
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{{semi-stub}}
  
 
[[Category: Software Concepts]]
 
[[Category: Software Concepts]]

Latest revision as of 17:44, 1 July 2020

An exception (more often condition) refers to facilities in some programming languages and operating systems to indicate the occurrence of some sort of error or un-expected event - e.g. 'divide by zero' or 'unexpected end-of-file'.

The term 'exception' is also often used for hardware-detected issues (e.g. in the Motorola 68000 Family), where a trap is the usual result; the term 'condition' is usually more general, and covers software-detected and generated issues. Software is said to raise or signal a condition.

When such an event happens, program execution is diverted to an condition handler for that specific condition, which is expected to deal with that condition.