In essence, namespace behaviors acted as hooks for update operations on
namespaces. Two behaviors were implemented:
- `NamespaceBehavior`: allows the update operation unless it acts on a value
that itself was explicitly marked as constant.
- `ConstNamespaceBehavior`: initially allows insert operations but marks the
individual values as const. Additionally provides a `Freeze()` member
function. After this was called, updates are rejected unless a special
`overrideFrozen` flag is set explicitly.
This marvel of object-oriented programming can be replaced with a simple bool.
This commit basically replaces `Namespace::m_Behavior` with
`Namespace::m_ConstValues` and inlines the behavior functions where they were
called. While doing so, the code was slightly simplified by assuming that
`m_ConstValues` is true if `m_Frozen` is true. This is similar to what the API
allowed in the old code as you could only freeze a `ConstNamespaceBehavior`.
However, this PR moves the `Freeze()` member function and the related
`m_Freeze` member variable to the `Namespace` class. So now the API allows any
namespace to be frozen. The new code also makes sense with the previously
mentioned simplification: a `Namespace` with `m_ConstValues = false` can be
modified without restrictions until `Freeze()` is called. When this is done, it
becomes read-only.
The changes outside of `namespace.*` just adapt the code to the slightly
changed API.
Julian Brost
Alexander A. Klimov
Michael Friedrich
Gunnar Beutner