TreeMutatorSizeTraits< TAR, SEL > Struct Template Reference

#include "lib/diff/tree-diff-traits.hpp"

Description

template<class TAR, typename SEL = void>
struct lib::diff::TreeMutatorSizeTraits< TAR, SEL >

Heuristics to guide the allocation for nested TreeMutator.

When applying a structural (tree) diff, the (otherwise undisclosed) target data structure needs to supply a TreeMutator implementation properly wired to the internal opaque data elements. Typically, this custom TreeMutator relies on several lambdas and closures, which require a variable and hard to guess amount of storage for back pointers and embedded parametrisation. More so, when the diff application opens nested scopes within the target data. The TreeDiffMutatorBinding relies on a (likewise opaque) ScopeManager implementation to maintain a stack of heap allocated buffers, where the mentioned nested TreeMutator implementations can be built and operated during the mutation process.

The default for buffer dimensions includes a safety margin and is thus quite expensive – even though this is just a temporary working buffer. Thus we offer a hook for explicit or partial specialisations to control the very common cases known to work with smaller buffer sizes.

future extensions

We might consider to make this system dynamic, in case buffer allocation for tree diff application becomes an issue in general. We might then guard the whole diff application location with try-catch blocks and allow thus for learning the right setting at runtime; obviously we'd then also have to memorise our findings somehow within the dynamic application configuration.

See also

tree-diff-application.hpp

DiffComplexApplication_test

Definition at line 88 of file tree-diff-traits.hpp.

Public Types
enum	{ siz = 200 }

Collaboration diagram for TreeMutatorSizeTraits< TAR, SEL >:

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The documentation for this struct was generated from the following file:

• tree-diff-traits.hpp