flow

Module nu.tree.flow.

Flow-aware wrapping primitives.

Generic, semantically-aware tools for injecting wrappers (Brackets, Policies, instrumentation) at the natural unit of mutation: the Flow. No fabric or boundary knowledge. Wrappers and predicates are caller-provided. Effect analysis (which Refs a subtree touches) lives in the sibling effects module.

is_flow

Predicate: node is a Flow.

tree.is_flow(node)

Path nu.tree.is_flow. Defined on nu.tree.flow, bound as a function. Builds bool.

Arguments

Undocumented: example.

wrap_flow_children

At each Flow node, replace every direct child with wrapper(child).

tree.wrap_flow_children(tree, wrapper, descend=None)

Path nu.tree.wrap_flow_children. Defined on nu.tree.flow, bound as a function. Builds Nu.

Walk is bottom-up: inner Flows are processed before outer ones, so by the time the outer Flow is reached, its inner Flow children already carry their per-branch wraps.

The Flow node itself is unchanged in shape. Only its children are swapped. Use this when the boundary unit is the Flow's branch, not the Flow as a whole.

descend: optional predicate. If it returns False for a node, that subtree is treated as opaque and recursion stops there. Use this to keep existing wrappers (e.g. Brackets) intact while still letting the outer Flow wrap them as a whole.

Arguments

Undocumented: example.

wrap_flows

Wrap outermost Flow nodes with wrapper(flow).

tree.wrap_flows(tree, wrapper, predicate=None)

Path nu.tree.wrap_flows. Defined on nu.tree.flow, bound as a function. Builds Nu.

Walks top-down. When a Flow (matching predicate if given) is found, calls wrapper(flow) and does not recurse inside. That subtree is claimed whole. Non-matching nodes are recursed into.

Use this to inject one boundary per outermost unit of mutation, respecting the algebraic structure already present in the tree.

Arguments

Undocumented: example.