class X::Assignment::RO

Exception thrown when trying to assign to something read-only

class X::Assignment::RO is Exception {}

Code like

sub f() { 42 };
f() = 'new value';  # throws an X::Assignment::RO 
CATCH { default { put .^name, ': ', .Str } };
# OUTPUT: «X::Assignment::RO: Cannot modify an immutable Any␤»

throws an exception of type X::Assignment::RO.

Methods

method typename

method typename(X::Assignment::RO:D: --> Str)

Returns the type name of the value on the left-hand side