Modern Math DivChecked

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DivChecked

Divides two integers, returning an empty Optional on division by zero or overflow.

Syntax

DivChecked( byval a as T, byval b as T ) as Optional( of T )

Notes

• Two failing cases, not one: division by zero, and the most negative value divided by -1 -- whose true quotient has no representation, exactly as with AbsChecked.
• That second case is the one hand-written guards forget; a bare if b <> 0 is not enough.
• There is no saturating or wrapping division, because neither has a defensible answer for a divide by zero.

Examples

#import "std/numeric"
using numeric

dim as int8 a = 10, b = 0
print DivChecked( a, b ).HasValue( )          '' false -- divide by zero

'' THE CASE A HAND-WRITTEN GUARD FORGETS: -128 \ -1 has no
'' representation in a BYTE
dim as int8 worst = -128, neg = -1
print DivChecked( worst, neg ).HasValue( )    '' false

dim as int8 c = 10, d = 3
print DivChecked( c, d ).Value( )             '' 3

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Library: Math Library
Category: Math Library
Documented under: Members