Difference between revisions of "Language Reference/Built-in entities/Operators"
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See also {{lang2|Terms|Operators|Operators}}. | |||
{|{{prettytable}} | {|{{prettytable}} | ||
|- | |- | ||
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! Description | ! Description | ||
! Remark | ! Remark | ||
|- | |||
| <vp>^</vp> | |||
| Power operation | |||
| Not defined for 64 bit integral numbers | |||
|- | |- | ||
| <vp>-</vp> (unary) | | <vp>-</vp> (unary) | ||
| Unary minus | | Unary minus | ||
| | | | ||
|- | |- | ||
| <vp>*</vp>, <vp>/</vp> | | <vp>*</vp>, <vp>/</vp> | ||
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| <vp>div</vp>, <vp>mod</vp> | | <vp>div</vp>, <vp>mod</vp> | ||
| The quotient and remainder of an integral division rounded towards minus infinity | | The quotient and remainder of an integral division rounded towards minus infinity | ||
| Not defined for | | Not defined for real's | ||
|- | |- | ||
| <vp>quot</vp>, <vp>rem</vp> | | <vp>quot</vp>, <vp>rem</vp> | ||
| The quotient and remainder of an integral division rounded towards zero | | The quotient and remainder of an integral division rounded towards zero | ||
| Not defined for | | Not defined for real's | ||
|- | |- | ||
| <vp>+</vp>, <vp>-</vp> | | <vp>+</vp>, <vp>-</vp> | ||
| Addition and subtraction | | Addition and subtraction | ||
| | |||
|- | |||
| <vp>otherwise</vp> | |||
| Otherwise expression | |||
| | | | ||
|} | |} | ||
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* The operators are listed from highest to lowest precedence | * The operators are listed from highest to lowest precedence | ||
* All division and multiplication operators have same precedence. | * All division and multiplication operators have same precedence. | ||
* The | * The power operator <vp>^</vp> and <vp>otherwise</vp> are right associative. | ||
* All other operators are left associative. | * All other operators are left associative. | ||
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==== Integral division ==== | ==== Integral division ==== | ||
<vp>div</vp> and <vp>quot</vp> | <vp>div</vp> and <vp>quot</vp> are different integral division operators. | ||
* <vp>div</vp> truncates towards minus infinite. <vp>mod</vp> is the remainder corresponding to <vp>div</vp>. | |||
* <vp>quot</vp> truncates towards zero. <vp>rem</vp> is the remainder corresponding to <vp>quot</vp>. | |||
For positive results <vp>div</vp> and <vp>quot</vp> have same functionality. | |||
The difference can be seen in this table: | |||
{|border="2" cellspacing="0" cellpadding="5" rules="all" style="border:solid 1px #AAAAAA; border-collapse:collapse; empty-cells:show; text-align: center;" | {|border="2" cellspacing="0" cellpadding="5" rules="all" style="border:solid 1px #AAAAAA; border-collapse:collapse; empty-cells:show; text-align: center;" | ||
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| <vp>-1</vp> | | <vp>-1</vp> | ||
|} | |} | ||
<noinclude>{{LanguageReferenceSubarticle|Built-in entities/Operators}}</noinclude> | |||
Latest revision as of 12:07, 4 August 2020
See also Operators.
| Operator | Description | Remark |
|---|---|---|
| ^ | Power operation | Not defined for 64 bit integral numbers |
| - (unary) | Unary minus | |
| *, / | Multiplication and division | |
| div, mod | The quotient and remainder of an integral division rounded towards minus infinity | Not defined for real's |
| quot, rem | The quotient and remainder of an integral division rounded towards zero | Not defined for real's |
| +, - | Addition and subtraction | |
| otherwise | Otherwise expression |
- The operators are listed from highest to lowest precedence
- All division and multiplication operators have same precedence.
- The power operator ^ and otherwise are right associative.
- All other operators are left associative.
All binary operators takes two arguments of same base type and returns a value of that base type. Operands and result may be converted using ordinary subtype rules.
Integral division
div and quot are different integral division operators.
- div truncates towards minus infinite. mod is the remainder corresponding to div.
- quot truncates towards zero. rem is the remainder corresponding to quot.
For positive results div and quot have same functionality.
The difference can be seen in this table:
| A | B | A div B | A mod B | A quot B | A rem B |
| 15 | 7 | 2 | 1 | 2 | 1 |
| -15 | 7 | -3 | 6 | -2 | -1 |
| 15 | -7 | -3 | -6 | -2 | 1 |
| -15 | -7 | 2 | -1 | 2 | -1 |