Difference between revisions of "Language Reference/Built-in entities/Operators"

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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 is right associative
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* 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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<vp>div</vp> and <vp>quot</vp> are different integral division operators.
 
<vp>div</vp> and <vp>quot</vp> are different integral division operators.
  
* <vp>div</vp> rounds towards minus infinite. <vp>mod</vp> is the remainder corresponding to <vp>div</vp>.
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* <vp>div</vp> truncates towards minus infinite. <vp>mod</vp> is the remainder corresponding to <vp>div</vp>.
* <vp>quot</vp> rounds towards zero. <vp>rem</vp> is the remainder corresponding to <vp>quot</vp>.
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* <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.
 
For positive results <vp>div</vp> and <vp>quot</vp> have same functionality.

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