src/commando.d(112,31): Error: `@safe` function `commando.Option.opAssign` cannot call `@system` constructor `std.variant.VariantN!32LU.VariantN.__ctor!bool.this`
/opt/dmd-safe/dmd/generated/linux/release/64/../../../../../phobos/std/variant.d(599,5):        `std.variant.VariantN!32LU.VariantN.__ctor!bool.this` is declared here
/opt/dmd-safe/dmd/dmd-safe failed with exit code 1.