Modern Finance CurrencyInvalid

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CurrencyInvalid

Returns the Invalid Currency, which overflow also produces; it never equals anything.

Syntax

CurrencyInvalid( ) as Currency

Notes

• Overflow lands here rather than raising, in the same style the chrono types use. A failed parse does not: CurrencyParse returns an empty Optional.
• Absorbing: arithmetic touching it yields Invalid, so one bad value in a long sum does not quietly become a plausible number.
• IsValid is the only correct test -- an Invalid does not compare equal to anything, itself included.

Examples

#import "std/money"
using money

dim as Currency bad = CurrencyInvalid( )
print bad.IsValid( )         '' false

'' Absorbing: it survives arithmetic rather than being papered over
dim as Currency ten = CurrencyFromInt( 10 )
print ( bad + ten ).IsValid( )                '' false

'' And it never compares equal, so IsValid is the test
print ( bad = CurrencyInvalid( ) )            '' false

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Library: Finance
Category: Finance
Documented under: Members