Data type: Difference between revisions
From Free Pascal wiki
Jump to navigationJump to search
No edit summary |
mNo edit summary |
||
Line 3: | Line 3: | ||
A '''data type''' is a classification of a variable or constant. There are certain data types that are predefined by any Pascal compiler (because you need them to make everything else). These are: | A '''data type''' is a classification of a variable or constant. There are certain data types that are predefined by any Pascal compiler (because you need them to make everything else). These are: | ||
* [[Byte|byte]] - an unsigned number in the range 0 to 255 | * [[Byte|byte]] - an unsigned number in the range 0 to 255. | ||
* [[Char|char]] - Single character | * [[Char|char]] - Single character. | ||
* [[Integer|integer]] - a whole number. | * [[Integer|integer]] - a whole number. FPC currently uses 4 bytes for integers. | ||
* [[Real|real]] - a number which may have a decimal point and possibly an exponent | * [[Real|real]] - a number which may have a decimal point and possibly an exponent. | ||
* [[Cardinal|cardinal]] - an unsigned whole number,ie it must be | * [[Cardinal|cardinal]] - an unsigned whole number,ie it must be positive. | ||
* [[Set|set]] - a collection of related elements; size depends on number of elements | * [[Set|set]] - a collection of related elements; size depends on number of elements. | ||
* [[Pointer|pointer]] - a reference to a location in memory, generally used for dynamic variables | * [[Pointer|pointer]] - a reference to a location in memory, generally used for dynamic variables. | ||
* [[Record|record]] - a combination of the above data types collected together | * [[Record|record]] - a combination of the above data types collected together. | ||
* [[Class|class]] | * [[Class|class]] | ||
* [[Object|object]] - a hybrid entity that may contain data and procedures to manipulate that data | * [[Object|object]] - a hybrid entity that may contain data and procedures to manipulate that data. | ||
Other data types are generally made with some combination of the above. FPC adds additional data types. | Other data types are generally made with some combination of the above. FPC adds additional data types. |
Revision as of 20:45, 25 January 2016
│
Deutsch (de) │
English (en) │
español (es) │
français (fr) │
Bahasa Indonesia (id) │
italiano (it) │
русский (ru) │
A data type is a classification of a variable or constant. There are certain data types that are predefined by any Pascal compiler (because you need them to make everything else). These are:
- byte - an unsigned number in the range 0 to 255.
- char - Single character.
- integer - a whole number. FPC currently uses 4 bytes for integers.
- real - a number which may have a decimal point and possibly an exponent.
- cardinal - an unsigned whole number,ie it must be positive.
- set - a collection of related elements; size depends on number of elements.
- pointer - a reference to a location in memory, generally used for dynamic variables.
- record - a combination of the above data types collected together.
- class
- object - a hybrid entity that may contain data and procedures to manipulate that data.
Other data types are generally made with some combination of the above. FPC adds additional data types.