No, there’s no way of doing this. For instance, if you return a List<string> (and it’s not immutable) then callers will be able to add entries. The normal way round this is to return an immutable wrapper, e.g. ReadOnlyCollection<T>. For other mutable types, you may need to clone the value before returning it. Note that … Read more
If it’s private and readonly, the benefit is that you can’t inadvertently change it from another part of that class after it is initialized. The readonly modifier ensures the field can only be given a value during its initialization or in its class constructor. If something functionally should not change after initialization, it’s always good … Read more
You could use pointer-events: none; to disable mouse DOM interaction (like click, hover, etc) on certain element. Example: div { pointer-events: none; } <div> <input type=”text” value=”value” /> <br /> <textarea>value</textarea> </div> However, even though pointer-events: none; is there, it’s still possible to make the cursor to be focus on the element (or it’s children). … Read more
The information is stored in sys.databases. SELECT name, is_read_only FROM sys.databases WHERE name=”MyDBNAme” GO –returns 1 in is_read_only when database is set to read-only mode.
In the current widely available implementation, ECMAScript 3 there is no support for real immutability. UPDATE: Nowadays, the ECMAScript 5 standard is widely supported. It adds the Object.seal and Object.freeze methods. The Object.seal method will prevent property additions, still allowing the user to write to or edit the existing properties. The Object.freeze method will completely … Read more
To expand on Ignacio’s answer: def counter(): count = 0 def c(): nonlocal count count += 1 return count return c x = counter() print([x(),x(),x()]) gives [1,2,3] in Python 3; invocations of counter() give independent counters. Other solutions – especially using itertools/yield are more idiomatic.
Use collections.Mapping e.g. import collections class DictWrapper(collections.Mapping): def __init__(self, data): self._data = data def __getitem__(self, key): return self._data[key] def __len__(self): return len(self._data) def __iter__(self): return iter(self._data)
The difference lies in the JIT for the new release of .NET, which apparently optimizes references to String.Empty by inlining a reference to a particular String instance rather than load the value stored in the Empty field. This is justified under the definition of the init-only constraint in ECMA-335 Partition I ยง8.6.1.2, which can be … Read more
var di = new DirectoryInfo(“SomeFolder”); di.Attributes &= ~FileAttributes.ReadOnly;
This is probably because static const double[] arr = { 1, 2, 3, 4, 5, 6, 7, 8, 9}; is in fact the same as saying static const double[] arr = new double[]{ 1, 2, 3, 4, 5, 6, 7, 8, 9}; A value assigned to a const has to be… const. Every reference type … Read more