class

NotImmutableErr

const class NotImmutableErr : Err

NotImmutableErr indicates using a mutable Obj where an immutable Obj is required. See Obj.isImmutable for the definition of immutability.

 constructors make

Construct with specified error message and optional root cause

 make new make(Str msg, Err? cause)

Construct with specified error message and optional root cause.

 Haxall 4.0.5 ∙ 24-Feb-2026 14:33 EST