```{index} single: Math::BigInt::FastCalc ``` # Math::BigInt::FastCalc ```{pperl-module-badges} Math::BigInt::FastCalc ``` The XS half of Math::BigInt::FastCalc 0.5020: the hot primitives of Math::BigInt's default library, in C. `Math/BigInt/FastCalc.pm` (served verbatim from lib/) is a subclass of Math::BigInt::Calc, which stores a number as an array of base-10**N "parts", least significant first. These XSUBs replace Calc's Perl for creating, copying, incrementing, decrementing, comparing and testing such arrays; everything else is Calc's. ```perl use Math::BigInt lib => 'FastCalc'; print Math::BigInt->new("123456789012345678901234567890") + 1; # 123456789012345678901234567891 ``` Nothing calls these XSUBs but the library itself. `Math::BigInt` uses FastCalc when asked to, with `lib => 'FastCalc'` (or `try` / `only`); its default library is plain `Math::BigInt::Calc`. ## Differences from upstream None.